history of computer research paper

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The History of Computing: A Very Short Introduction

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This book describes the central events, machines, and people in the history of computing, and traces how innovation has brought us from pebbles used for counting, to the modern age of the computer. It has a strong historiographical theme that offers a new perspective on how to understand the historical narratives we have constructed, and examines the unspoken assumptions that underpin them. It describes inventions, pioneers, milestone systems, and the context of their use. It starts with counting, and traces change through calculating aids, mechanical calculation, and automatic electronic computation, both digital and analogue. It shows how four threads—calculation, automatic computing, information management, and communications—converged to create the ‘information age’. It examines three master narratives in established histories that are used as aids to marshal otherwise unmanageable levels detail. The treatment is rooted in the principal episodes that make up canonical histories of computing.

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The History of Digital Computers

• Published 1974
• Computer Science, History

11 Citations

An annotated bibliography on the origins of digital computers.

• Highly Influenced
• 12 Excerpts

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The Evolution of Computers

Proceedings of the 5th International Conference on Communication and Information Processing (ICCIP)- 2023

9 Pages Posted: 9 Jan 2024

Sudarshan Kakad

Nutan college of engineering and research, vishnupuri, talegaon dabhade, pune – 410507, india., vaibhav kale, atharv kakare, aditya kalokhe, archana yewale.

Date Written: June 9, 2023

The evolution of computers has been one of the most transformative journeys in human history. This review paper provides a comprehensive examination of the development of computers from their early beginnings to the present day, shedding light on the major milestones, technological breakthroughs, and their profound implications on society. The paper commences with an exploration of the origins of computers, starting from the mechanical calculators of the 19th century to the emergence of early electronic computers in the mid-20th century. It highlights significant contributions by pioneers such as Charles Babbage, Alan Turing, and John von Neumann, who laid the foundations for the digital computing era. The subsequent sections focus on the revolutionary advancements that have shaped the evolution of computers. This includes the advent of transistors and integrated circuits, leading to the development of smaller, faster, and more powerful computers. The rise of personal computers in the 1970s and 1980s democratized computing, empowering individuals and businesses alike. The review also delves into the progression of computer architectures, the mainframe and minicomputer. Overall, this review paper provides a comprehensive overview of the evolution of computers, capturing the key milestones, technological advancements, and societal implications. It serves as a valuable resource for researchers, educators, and technology enthusiasts seeking to understand the transformative journey of computers.

Keywords: computers, evolution, history, inventions

JEL Classification: C0

Suggested Citation: Suggested Citation

Archana Yewale (Contact Author)

Nutan college of engineering and research, vishnupuri, talegaon dabhade, pune – 410507, india. ( email ), do you have a job opening that you would like to promote on ssrn, paper statistics, related ejournals, information theory & research ejournal.

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History of Science & Environment eJournal

5th international conference on communication & information processing (iccip) 2023.

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History of computers: A brief timeline

The history of computers began with primitive designs in the early 19th century and went on to change the world during the 20th century.

• 2000-present day

Additional resources

The history of computers goes back over 200 years. At first theorized by mathematicians and entrepreneurs, during the 19th century mechanical calculating machines were designed and built to solve the increasingly complex number-crunching challenges. The advancement of technology enabled ever more-complex computers by the early 20th century, and computers became larger and more powerful.

Today, computers are almost unrecognizable from designs of the 19th century, such as Charles Babbage's Analytical Engine — or even from the huge computers of the 20th century that occupied whole rooms, such as the Electronic Numerical Integrator and Calculator.  

Here's a brief history of computers, from their primitive number-crunching origins to the powerful modern-day machines that surf the Internet, run games and stream multimedia. 

19th century

1801: Joseph Marie Jacquard, a French merchant and inventor invents a loom that uses punched wooden cards to automatically weave fabric designs. Early computers would use similar punch cards.

1821: English mathematician Charles Babbage conceives of a steam-driven calculating machine that would be able to compute tables of numbers. Funded by the British government, the project, called the "Difference Engine" fails due to the lack of technology at the time, according to the University of Minnesota . 

1848: Ada Lovelace, an English mathematician and the daughter of poet Lord Byron, writes the world's first computer program. According to Anna Siffert, a professor of theoretical mathematics at the University of Münster in Germany, Lovelace writes the first program while translating a paper on Babbage's Analytical Engine from French into English. "She also provides her own comments on the text. Her annotations, simply called "notes," turn out to be three times as long as the actual transcript," Siffert wrote in an article for The Max Planck Society . "Lovelace also adds a step-by-step description for computation of Bernoulli numbers with Babbage's machine — basically an algorithm — which, in effect, makes her the world's first computer programmer." Bernoulli numbers are a sequence of rational numbers often used in computation.

1853: Swedish inventor Per Georg Scheutz and his son Edvard design the world's first printing calculator. The machine is significant for being the first to "compute tabular differences and print the results," according to Uta C. Merzbach's book, " Georg Scheutz and the First Printing Calculator " (Smithsonian Institution Press, 1977).

1890: Herman Hollerith designs a punch-card system to help calculate the 1890 U.S. Census. The machine,  saves the government several years of calculations, and the U.S. taxpayer approximately $5 million, according to Columbia University  Hollerith later establishes a company that will eventually become International Business Machines Corporation ( IBM ).

Early 20th century

1931: At the Massachusetts Institute of Technology (MIT), Vannevar Bush invents and builds the Differential Analyzer, the first large-scale automatic general-purpose mechanical analog computer, according to Stanford University . 

1936: Alan Turing , a British scientist and mathematician, presents the principle of a universal machine, later called the Turing machine, in a paper called "On Computable Numbers…" according to Chris Bernhardt's book " Turing's Vision " (The MIT Press, 2017). Turing machines are capable of computing anything that is computable. The central concept of the modern computer is based on his ideas. Turing is later involved in the development of the Turing-Welchman Bombe, an electro-mechanical device designed to decipher Nazi codes during World War II, according to the UK's National Museum of Computing . 

1937: John Vincent Atanasoff, a professor of physics and mathematics at Iowa State University, submits a grant proposal to build the first electric-only computer, without using gears, cams, belts or shafts.

1939: David Packard and Bill Hewlett found the Hewlett Packard Company in Palo Alto, California. The pair decide the name of their new company by the toss of a coin, and Hewlett-Packard's first headquarters are in Packard's garage, according to MIT . 

1941: German inventor and engineer Konrad Zuse completes his Z3 machine, the world's earliest digital computer, according to Gerard O'Regan's book " A Brief History of Computing " (Springer, 2021). The machine was destroyed during a bombing raid on Berlin during World War II. Zuse fled the German capital after the defeat of Nazi Germany and later released the world's first commercial digital computer, the Z4, in 1950, according to O'Regan. 

1941: Atanasoff and his graduate student, Clifford Berry, design the first digital electronic computer in the U.S., called the Atanasoff-Berry Computer (ABC). This marks the first time a computer is able to store information on its main memory, and is capable of performing one operation every 15 seconds, according to the book " Birthing the Computer " (Cambridge Scholars Publishing, 2016)

1945: Two professors at the University of Pennsylvania, John Mauchly and J. Presper Eckert, design and build the Electronic Numerical Integrator and Calculator (ENIAC). The machine is the first "automatic, general-purpose, electronic, decimal, digital computer," according to Edwin D. Reilly's book "Milestones in Computer Science and Information Technology" (Greenwood Press, 2003). 

1946: Mauchly and Presper leave the University of Pennsylvania and receive funding from the Census Bureau to build the UNIVAC, the first commercial computer for business and government applications.

1947: William Shockley, John Bardeen and Walter Brattain of Bell Laboratories invent the transistor . They discover how to make an electric switch with solid materials and without the need for a vacuum.

1949: A team at the University of Cambridge develops the Electronic Delay Storage Automatic Calculator (EDSAC), "the first practical stored-program computer," according to O'Regan. "EDSAC ran its first program in May 1949 when it calculated a table of squares and a list of prime numbers ," O'Regan wrote. In November 1949, scientists with the Council of Scientific and Industrial Research (CSIR), now called CSIRO, build Australia's first digital computer called the Council for Scientific and Industrial Research Automatic Computer (CSIRAC). CSIRAC is the first digital computer in the world to play music, according to O'Regan.

Late 20th century

1953: Grace Hopper develops the first computer language, which eventually becomes known as COBOL, which stands for COmmon, Business-Oriented Language according to the National Museum of American History . Hopper is later dubbed the "First Lady of Software" in her posthumous Presidential Medal of Freedom citation. Thomas Johnson Watson Jr., son of IBM CEO Thomas Johnson Watson Sr., conceives the IBM 701 EDPM to help the United Nations keep tabs on Korea during the war.

1954: John Backus and his team of programmers at IBM publish a paper describing their newly created FORTRAN programming language, an acronym for FORmula TRANslation, according to MIT .

1958: Jack Kilby and Robert Noyce unveil the integrated circuit, known as the computer chip. Kilby is later awarded the Nobel Prize in Physics for his work.

1968: Douglas Engelbart reveals a prototype of the modern computer at the Fall Joint Computer Conference, San Francisco. His presentation, called "A Research Center for Augmenting Human Intellect" includes a live demonstration of his computer, including a mouse and a graphical user interface (GUI), according to the Doug Engelbart Institute . This marks the development of the computer from a specialized machine for academics to a technology that is more accessible to the general public.

1969: Ken Thompson, Dennis Ritchie and a group of other developers at Bell Labs produce UNIX, an operating system that made "large-scale networking of diverse computing systems — and the internet — practical," according to Bell Labs .. The team behind UNIX continued to develop the operating system using the C programming language, which they also optimized. 

1970: The newly formed Intel unveils the Intel 1103, the first Dynamic Access Memory (DRAM) chip.

1971: A team of IBM engineers led by Alan Shugart invents the "floppy disk," enabling data to be shared among different computers.

1972: Ralph Baer, a German-American engineer, releases Magnavox Odyssey, the world's first home game console, in September 1972 , according to the Computer Museum of America . Months later, entrepreneur Nolan Bushnell and engineer Al Alcorn with Atari release Pong, the world's first commercially successful video game. 

1973: Robert Metcalfe, a member of the research staff for Xerox, develops Ethernet for connecting multiple computers and other hardware.

1977: The Commodore Personal Electronic Transactor (PET), is released onto the home computer market, featuring an MOS Technology 8-bit 6502 microprocessor, which controls the screen, keyboard and cassette player. The PET is especially successful in the education market, according to O'Regan.

1975: The magazine cover of the January issue of "Popular Electronics" highlights the Altair 8080 as the "world's first minicomputer kit to rival commercial models." After seeing the magazine issue, two "computer geeks," Paul Allen and Bill Gates, offer to write software for the Altair, using the new BASIC language. On April 4, after the success of this first endeavor, the two childhood friends form their own software company, Microsoft.

1976: Steve Jobs and Steve Wozniak co-found Apple Computer on April Fool's Day. They unveil Apple I, the first computer with a single-circuit board and ROM (Read Only Memory), according to MIT .

1977: Radio Shack began its initial production run of 3,000 TRS-80 Model 1 computers — disparagingly known as the "Trash 80" — priced at $599, according to the National Museum of American History. Within a year, the company took 250,000 orders for the computer, according to the book " How TRS-80 Enthusiasts Helped Spark the PC Revolution " (The Seeker Books, 2007).

1977: The first West Coast Computer Faire is held in San Francisco. Jobs and Wozniak present the Apple II computer at the Faire, which includes color graphics and features an audio cassette drive for storage.

1978: VisiCalc, the first computerized spreadsheet program is introduced.

1979: MicroPro International, founded by software engineer Seymour Rubenstein, releases WordStar, the world's first commercially successful word processor. WordStar is programmed by Rob Barnaby, and includes 137,000 lines of code, according to Matthew G. Kirschenbaum's book " Track Changes: A Literary History of Word Processing " (Harvard University Press, 2016).

1981: "Acorn," IBM's first personal computer, is released onto the market at a price point of $1,565, according to IBM. Acorn uses the MS-DOS operating system from Windows. Optional features include a display, printer, two diskette drives, extra memory, a game adapter and more.

1983: The Apple Lisa, standing for "Local Integrated Software Architecture" but also the name of Steve Jobs' daughter, according to the National Museum of American History ( NMAH ), is the first personal computer to feature a GUI. The machine also includes a drop-down menu and icons. Also this year, the Gavilan SC is released and is the first portable computer with a flip-form design and the very first to be sold as a "laptop."

1984: The Apple Macintosh is announced to the world during a Superbowl advertisement. The Macintosh is launched with a retail price of $2,500, according to the NMAH. 

1985 : As a response to the Apple Lisa's GUI, Microsoft releases Windows in November 1985, the Guardian reported . Meanwhile, Commodore announces the Amiga 1000.

1989: Tim Berners-Lee, a British researcher at the European Organization for Nuclear Research ( CERN ), submits his proposal for what would become the World Wide Web. His paper details his ideas for Hyper Text Markup Language (HTML), the building blocks of the Web. 

1993: The Pentium microprocessor advances the use of graphics and music on PCs.

1996: Sergey Brin and Larry Page develop the Google search engine at Stanford University.

1997: Microsoft invests $150 million in Apple, which at the time is struggling financially.  This investment ends an ongoing court case in which Apple accused Microsoft of copying its operating system. 

1999: Wi-Fi, the abbreviated term for "wireless fidelity" is developed, initially covering a distance of up to 300 feet (91 meters) Wired reported . 

21st century

2001: Mac OS X, later renamed OS X then simply macOS, is released by Apple as the successor to its standard Mac Operating System. OS X goes through 16 different versions, each with "10" as its title, and the first nine iterations are nicknamed after big cats, with the first being codenamed "Cheetah," TechRadar reported.  

2003: AMD's Athlon 64, the first 64-bit processor for personal computers, is released to customers. 

2004: The Mozilla Corporation launches Mozilla Firefox 1.0. The Web browser is one of the first major challenges to Internet Explorer, owned by Microsoft. During its first five years, Firefox exceeded a billion downloads by users, according to the Web Design Museum . 

2005: Google buys Android, a Linux-based mobile phone operating system

2006: The MacBook Pro from Apple hits the shelves. The Pro is the company's first Intel-based, dual-core mobile computer. 

2009: Microsoft launches Windows 7 on July 22. The new operating system features the ability to pin applications to the taskbar, scatter windows away by shaking another window, easy-to-access jumplists, easier previews of tiles and more, TechRadar reported .  

2010: The iPad, Apple's flagship handheld tablet, is unveiled.

2011: Google releases the Chromebook, which runs on Google Chrome OS.

2015: Apple releases the Apple Watch. Microsoft releases Windows 10.

2016: The first reprogrammable quantum computer was created. "Until now, there hasn't been any quantum-computing platform that had the capability to program new algorithms into their system. They're usually each tailored to attack a particular algorithm," said study lead author Shantanu Debnath, a quantum physicist and optical engineer at the University of Maryland, College Park.

2017: The Defense Advanced Research Projects Agency (DARPA) is developing a new "Molecular Informatics" program that uses molecules as computers. "Chemistry offers a rich set of properties that we may be able to harness for rapid, scalable information storage and processing," Anne Fischer, program manager in DARPA's Defense Sciences Office, said in a statement. "Millions of molecules exist, and each molecule has a unique three-dimensional atomic structure as well as variables such as shape, size, or even color. This richness provides a vast design space for exploring novel and multi-value ways to encode and process data beyond the 0s and 1s of current logic-based, digital architectures."

2019: A team at Google became the first to demonstrate quantum supremacy — creating a quantum computer that could feasibly outperform the most powerful classical computer — albeit for a very specific problem with no practical real-world application. The described the computer, dubbed "Sycamore" in a paper that same year in the journal Nature . Achieving quantum advantage – in which a quantum computer solves a problem with real-world applications faster than the most powerful classical computer —  is still a ways off. 

2022: The first exascale supercomputer, and the world's fastest, Frontier, went online at the Oak Ridge Leadership Computing Facility (OLCF) in Tennessee. Built by Hewlett Packard Enterprise (HPE) at the cost of $600 million, Frontier uses nearly 10,000 AMD EPYC 7453 64-core CPUs alongside nearly 40,000 AMD Radeon Instinct MI250X GPUs. This machine ushered in the era of exascale computing, which refers to systems that can reach more than one exaFLOP of power – used to measure the performance of a system. Only one machine – Frontier – is currently capable of reaching such levels of performance. It is currently being used as a tool to aid scientific discovery.

What is the first computer in history?

Charles Babbage's Difference Engine, designed in the 1820s, is considered the first "mechanical" computer in history, according to the Science Museum in the U.K . Powered by steam with a hand crank, the machine calculated a series of values and printed the results in a table. 

What are the five generations of computing?

The "five generations of computing" is a framework for assessing the entire history of computing and the key technological advancements throughout it. 

The first generation, spanning the 1940s to the 1950s, covered vacuum tube-based machines. The second then progressed to incorporate transistor-based computing between the 50s and the 60s. In the 60s and 70s, the third generation gave rise to integrated circuit-based computing. We are now in between the fourth and fifth generations of computing, which are microprocessor-based and AI-based computing.

What is the most powerful computer in the world?

As of November 2023, the most powerful computer in the world is the Frontier supercomputer . The machine, which can reach a performance level of up to 1.102 exaFLOPS, ushered in the age of exascale computing in 2022 when it went online at Tennessee's  Oak Ridge Leadership Computing Facility (OLCF) 

There is, however, a potentially more powerful supercomputer waiting in the wings in the form of the Aurora supercomputer, which is housed at the Argonne National Laboratory (ANL) outside of Chicago.  Aurora went online in November 2023. Right now, it lags far behind Frontier, with performance levels of just 585.34 petaFLOPS (roughly half the performance of Frontier), although it's still not finished. When work is completed, the supercomputer is expected to reach performance levels higher than 2 exaFLOPS.

What was the first killer app?

Killer apps are widely understood to be those so essential that they are core to the technology they run on. There have been so many through the years – from Word for Windows in 1989 to iTunes in 2001 to social media apps like WhatsApp in more recent years

Several pieces of software may stake a claim to be the first killer app, but there is a broad consensus that VisiCalc, a spreadsheet program created by VisiCorp and originally released for the Apple II in 1979, holds that title. Steve Jobs even credits this app for propelling the Apple II to become the success it was, according to co-creator Dan Bricklin .

• Fortune: A Look Back At 40 Years of Apple
• The New Yorker: The First Windows
• " A Brief History of Computing " by Gerard O'Regan (Springer, 2021)

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Timothy is Editor in Chief of print and digital magazines All About History and History of War . He has previously worked on sister magazine All About Space , as well as photography and creative brands including Digital Photographer and 3D Artist . He has also written for How It Works magazine, several history bookazines and has a degree in English Literature from Bath Spa University . 

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The Modern History of Computing

Historically, computers were human clerks who calculated in accordance with effective methods. These human computers did the sorts of calculation nowadays carried out by electronic computers, and many thousands of them were employed in commerce, government, and research establishments. The term computing machine , used increasingly from the 1920s, refers to any machine that does the work of a human computer, i.e., any machine that calculates in accordance with effective methods. During the late 1940s and early 1950s, with the advent of electronic computing machines, the phrase ‘computing machine’ gradually gave way simply to ‘computer’, initially usually with the prefix ‘electronic’ or ‘digital’. This entry surveys the history of these machines.

• Analog Computers

The Universal Turing Machine

Electromechanical versus electronic computation, turing's automatic computing engine, the manchester machine, eniac and edvac, other notable early computers, high-speed memory, other internet resources, related entries.

Charles Babbage was Lucasian Professor of Mathematics at Cambridge University from 1828 to 1839 (a post formerly held by Isaac Newton). Babbage's proposed Difference Engine was a special-purpose digital computing machine for the automatic production of mathematical tables (such as logarithm tables, tide tables, and astronomical tables). The Difference Engine consisted entirely of mechanical components — brass gear wheels, rods, ratchets, pinions, etc. Numbers were represented in the decimal system by the positions of 10-toothed metal wheels mounted in columns. Babbage exhibited a small working model in 1822. He never completed the full-scale machine that he had designed but did complete several fragments. The largest — one ninth of the complete calculator — is on display in the London Science Museum. Babbage used it to perform serious computational work, calculating various mathematical tables. In 1990, Babbage's Difference Engine No. 2 was finally built from Babbage's designs and is also on display at the London Science Museum.

The Swedes Georg and Edvard Scheutz (father and son) constructed a modified version of Babbage's Difference Engine. Three were made, a prototype and two commercial models, one of these being sold to an observatory in Albany, New York, and the other to the Registrar-General's office in London, where it calculated and printed actuarial tables.

Babbage's proposed Analytical Engine, considerably more ambitious than the Difference Engine, was to have been a general-purpose mechanical digital computer. The Analytical Engine was to have had a memory store and a central processing unit (or ‘mill’) and would have been able to select from among alternative actions consequent upon the outcome of its previous actions (a facility nowadays known as conditional branching). The behaviour of the Analytical Engine would have been controlled by a program of instructions contained on punched cards connected together with ribbons (an idea that Babbage had adopted from the Jacquard weaving loom). Babbage emphasised the generality of the Analytical Engine, saying ‘the conditions which enable a finite machine to make calculations of unlimited extent are fulfilled in the Analytical Engine’ (Babbage [1994], p. 97).

Babbage worked closely with Ada Lovelace, daughter of the poet Byron, after whom the modern programming language ADA is named. Lovelace foresaw the possibility of using the Analytical Engine for non-numeric computation, suggesting that the Engine might even be capable of composing elaborate pieces of music.

A large model of the Analytical Engine was under construction at the time of Babbage's death in 1871 but a full-scale version was never built. Babbage's idea of a general-purpose calculating engine was never forgotten, especially at Cambridge, and was on occasion a lively topic of mealtime discussion at the war-time headquarters of the Government Code and Cypher School, Bletchley Park, Buckinghamshire, birthplace of the electronic digital computer.

Analog computers

The earliest computing machines in wide use were not digital but analog. In analog representation, properties of the representational medium ape (or reflect or model) properties of the represented state-of-affairs. (In obvious contrast, the strings of binary digits employed in digital representation do not represent by means of possessing some physical property — such as length — whose magnitude varies in proportion to the magnitude of the property that is being represented.) Analog representations form a diverse class. Some examples: the longer a line on a road map, the longer the road that the line represents; the greater the number of clear plastic squares in an architect's model, the greater the number of windows in the building represented; the higher the pitch of an acoustic depth meter, the shallower the water. In analog computers, numerical quantities are represented by, for example, the angle of rotation of a shaft or a difference in electrical potential. Thus the output voltage of the machine at a time might represent the momentary speed of the object being modelled.

As the case of the architect's model makes plain, analog representation may be discrete in nature (there is no such thing as a fractional number of windows). Among computer scientists, the term ‘analog’ is sometimes used narrowly, to indicate representation of one continuously-valued quantity by another (e.g., speed by voltage). As Brian Cantwell Smith has remarked:

‘Analog’ should … be a predicate on a representation whose structure corresponds to that of which it represents … That continuous representations should historically have come to be called analog presumably betrays the recognition that, at the levels at which it matters to us, the world is more foundationally continuous than it is discrete. (Smith [1991], p. 271)

James Thomson, brother of Lord Kelvin, invented the mechanical wheel-and-disc integrator that became the foundation of analog computation (Thomson [1876]). The two brothers constructed a device for computing the integral of the product of two given functions, and Kelvin described (although did not construct) general-purpose analog machines for integrating linear differential equations of any order and for solving simultaneous linear equations. Kelvin's most successful analog computer was his tide predicting machine, which remained in use at the port of Liverpool until the 1960s. Mechanical analog devices based on the wheel-and-disc integrator were in use during World War I for gunnery calculations. Following the war, the design of the integrator was considerably improved by Hannibal Ford (Ford [1919]).

Stanley Fifer reports that the first semi-automatic mechanical analog computer was built in England by the Manchester firm of Metropolitan Vickers prior to 1930 (Fifer [1961], p. 29); however, I have so far been unable to verify this claim. In 1931, Vannevar Bush, working at MIT, built the differential analyser, the first large-scale automatic general-purpose mechanical analog computer. Bush's design was based on the wheel and disc integrator. Soon copies of his machine were in use around the world (including, at Cambridge and Manchester Universities in England, differential analysers built out of kit-set Meccano, the once popular engineering toy).

It required a skilled mechanic equipped with a lead hammer to set up Bush's mechanical differential analyser for each new job. Subsequently, Bush and his colleagues replaced the wheel-and-disc integrators and other mechanical components by electromechanical, and finally by electronic, devices.

A differential analyser may be conceptualised as a collection of ‘black boxes’ connected together in such a way as to allow considerable feedback. Each box performs a fundamental process, for example addition, multiplication of a variable by a constant, and integration. In setting up the machine for a given task, boxes are connected together so that the desired set of fundamental processes is executed. In the case of electrical machines, this was done typically by plugging wires into sockets on a patch panel (computing machines whose function is determined in this way are referred to as ‘program-controlled’).

Since all the boxes work in parallel, an electronic differential analyser solves sets of equations very quickly. Against this has to be set the cost of massaging the problem to be solved into the form demanded by the analog machine, and of setting up the hardware to perform the desired computation. A major drawback of analog computation is the higher cost, relative to digital machines, of an increase in precision. During the 1960s and 1970s, there was considerable interest in ‘hybrid’ machines, where an analog section is controlled by and programmed via a digital section. However, such machines are now a rarity.

In 1936, at Cambridge University, Turing invented the principle of the modern computer. He described an abstract digital computing machine consisting of a limitless memory and a scanner that moves back and forth through the memory, symbol by symbol, reading what it finds and writing further symbols (Turing [1936]). The actions of the scanner are dictated by a program of instructions that is stored in the memory in the form of symbols. This is Turing's stored-program concept, and implicit in it is the possibility of the machine operating on and modifying its own program. (In London in 1947, in the course of what was, so far as is known, the earliest public lecture to mention computer intelligence, Turing said, ‘What we want is a machine that can learn from experience’, adding that the ‘possibility of letting the machine alter its own instructions provides the mechanism for this’ (Turing [1947] p. 393). Turing's computing machine of 1936 is now known simply as the universal Turing machine. Cambridge mathematician Max Newman remarked that right from the start Turing was interested in the possibility of actually building a computing machine of the sort that he had described (Newman in interview with Christopher Evans in Evans [197?].

From the start of the Second World War Turing was a leading cryptanalyst at the Government Code and Cypher School, Bletchley Park. Here he became familiar with Thomas Flowers' work involving large-scale high-speed electronic switching (described below). However, Turing could not turn to the project of building an electronic stored-program computing machine until the cessation of hostilities in Europe in 1945.

During the wartime years Turing did give considerable thought to the question of machine intelligence. Colleagues at Bletchley Park recall numerous off-duty discussions with him on the topic, and at one point Turing circulated a typewritten report (now lost) setting out some of his ideas. One of these colleagues, Donald Michie (who later founded the Department of Machine Intelligence and Perception at the University of Edinburgh), remembers Turing talking often about the possibility of computing machines (1) learning from experience and (2) solving problems by means of searching through the space of possible solutions, guided by rule-of-thumb principles (Michie in interview with Copeland, 1995). The modern term for the latter idea is ‘heuristic search’, a heuristic being any rule-of-thumb principle that cuts down the amount of searching required in order to find a solution to a problem. At Bletchley Park Turing illustrated his ideas on machine intelligence by reference to chess. Michie recalls Turing experimenting with heuristics that later became common in chess programming (in particular minimax and best-first).

Further information about Turing and the computer, including his wartime work on codebreaking and his thinking about artificial intelligence and artificial life, can be found in Copeland 2004.

With some exceptions — including Babbage's purely mechanical engines, and the finger-powered National Accounting Machine - early digital computing machines were electromechanical. That is to say, their basic components were small, electrically-driven, mechanical switches called ‘relays’. These operate relatively slowly, whereas the basic components of an electronic computer — originally vacuum tubes (valves) — have no moving parts save electrons and so operate extremely fast. Electromechanical digital computing machines were built before and during the second world war by (among others) Howard Aiken at Harvard University, George Stibitz at Bell Telephone Laboratories, Turing at Princeton University and Bletchley Park, and Konrad Zuse in Berlin. To Zuse belongs the honour of having built the first working general-purpose program-controlled digital computer. This machine, later called the Z3, was functioning in 1941. (A program-controlled computer, as opposed to a stored-program computer, is set up for a new task by re-routing wires, by means of plugs etc.)

Relays were too slow and unreliable a medium for large-scale general-purpose digital computation (although Aiken made a valiant effort). It was the development of high-speed digital techniques using vacuum tubes that made the modern computer possible.

The earliest extensive use of vacuum tubes for digital data-processing appears to have been by the engineer Thomas Flowers, working in London at the British Post Office Research Station at Dollis Hill. Electronic equipment designed by Flowers in 1934, for controlling the connections between telephone exchanges, went into operation in 1939, and involved between three and four thousand vacuum tubes running continuously. In 1938–1939 Flowers worked on an experimental electronic digital data-processing system, involving a high-speed data store. Flowers' aim, achieved after the war, was that electronic equipment should replace existing, less reliable, systems built from relays and used in telephone exchanges. Flowers did not investigate the idea of using electronic equipment for numerical calculation, but has remarked that at the outbreak of war with Germany in 1939 he was possibly the only person in Britain who realized that vacuum tubes could be used on a large scale for high-speed digital computation. (See Copeland 2006 for m more information on Flowers' work.)

The earliest comparable use of vacuum tubes in the U.S. seems to have been by John Atanasoff at what was then Iowa State College (now University). During the period 1937–1942 Atanasoff developed techniques for using vacuum tubes to perform numerical calculations digitally. In 1939, with the assistance of his student Clifford Berry, Atanasoff began building what is sometimes called the Atanasoff-Berry Computer, or ABC, a small-scale special-purpose electronic digital machine for the solution of systems of linear algebraic equations. The machine contained approximately 300 vacuum tubes. Although the electronic part of the machine functioned successfully, the computer as a whole never worked reliably, errors being introduced by the unsatisfactory binary card-reader. Work was discontinued in 1942 when Atanasoff left Iowa State.

The first fully functioning electronic digital computer was Colossus, used by the Bletchley Park cryptanalysts from February 1944.

From very early in the war the Government Code and Cypher School (GC&CS) was successfully deciphering German radio communications encoded by means of the Enigma system, and by early 1942 about 39,000 intercepted messages were being decoded each month, thanks to electromechanical machines known as ‘bombes’. These were designed by Turing and Gordon Welchman (building on earlier work by Polish cryptanalysts).

During the second half of 1941, messages encoded by means of a totally different method began to be intercepted. This new cipher machine, code-named ‘Tunny’ by Bletchley Park, was broken in April 1942 and current traffic was read for the first time in July of that year. Based on binary teleprinter code, Tunny was used in preference to Morse-based Enigma for the encryption of high-level signals, for example messages from Hitler and members of the German High Command.

The need to decipher this vital intelligence as rapidly as possible led Max Newman to propose in November 1942 (shortly after his recruitment to GC&CS from Cambridge University) that key parts of the decryption process be automated, by means of high-speed electronic counting devices. The first machine designed and built to Newman's specification, known as the Heath Robinson, was relay-based with electronic circuits for counting. (The electronic counters were designed by C.E. Wynn-Williams, who had been using thyratron tubes in counting circuits at the Cavendish Laboratory, Cambridge, since 1932 [Wynn-Williams 1932].) Installed in June 1943, Heath Robinson was unreliable and slow, and its high-speed paper tapes were continually breaking, but it proved the worth of Newman's idea. Flowers recommended that an all-electronic machine be built instead, but he received no official encouragement from GC&CS. Working independently at the Post Office Research Station at Dollis Hill, Flowers quietly got on with constructing the world's first large-scale programmable electronic digital computer. Colossus I was delivered to Bletchley Park in January 1943.

By the end of the war there were ten Colossi working round the clock at Bletchley Park. From a cryptanalytic viewpoint, a major difference between the prototype Colossus I and the later machines was the addition of the so-called Special Attachment, following a key discovery by cryptanalysts Donald Michie and Jack Good. This broadened the function of Colossus from ‘wheel setting’ — i.e., determining the settings of the encoding wheels of the Tunny machine for a particular message, given the ‘patterns’ of the wheels — to ‘wheel breaking’, i.e., determining the wheel patterns themselves. The wheel patterns were eventually changed daily by the Germans on each of the numerous links between the German Army High Command and Army Group commanders in the field. By 1945 there were as many 30 links in total. About ten of these were broken and read regularly.

Colossus I contained approximately 1600 vacuum tubes and each of the subsequent machines approximately 2400 vacuum tubes. Like the smaller ABC, Colossus lacked two important features of modern computers. First, it had no internally stored programs. To set it up for a new task, the operator had to alter the machine's physical wiring, using plugs and switches. Second, Colossus was not a general-purpose machine, being designed for a specific cryptanalytic task involving counting and Boolean operations.

F.H. Hinsley, official historian of GC&CS, has estimated that the war in Europe was shortened by at least two years as a result of the signals intelligence operation carried out at Bletchley Park, in which Colossus played a major role. Most of the Colossi were destroyed once hostilities ceased. Some of the electronic panels ended up at Newman's Computing Machine Laboratory in Manchester (see below), all trace of their original use having been removed. Two Colossi were retained by GC&CS (renamed GCHQ following the end of the war). The last Colossus is believed to have stopped running in 1960.

Those who knew of Colossus were prohibited by the Official Secrets Act from sharing their knowledge. Until the 1970s, few had any idea that electronic computation had been used successfully during the second world war. In 1970 and 1975, respectively, Good and Michie published notes giving the barest outlines of Colossus. By 1983, Flowers had received clearance from the British Government to publish a partial account of the hardware of Colossus I. Details of the later machines and of the Special Attachment, the uses to which the Colossi were put, and the cryptanalytic algorithms that they ran, have only recently been declassified. (For the full account of Colossus and the attack on Tunny see Copeland 2006.)

To those acquainted with the universal Turing machine of 1936, and the associated stored-program concept, Flowers' racks of digital electronic equipment were proof of the feasibility of using large numbers of vacuum tubes to implement a high-speed general-purpose stored-program computer. The war over, Newman lost no time in establishing the Royal Society Computing Machine Laboratory at Manchester University for precisely that purpose. A few months after his arrival at Manchester, Newman wrote as follows to the Princeton mathematician John von Neumann (February 1946):

I am … hoping to embark on a computing machine section here, having got very interested in electronic devices of this kind during the last two or three years. By about eighteen months ago I had decided to try my hand at starting up a machine unit when I got out. … I am of course in close touch with Turing.

Turing and Newman were thinking along similar lines. In 1945 Turing joined the National Physical Laboratory (NPL) in London, his brief to design and develop an electronic stored-program digital computer for scientific work. (Artificial Intelligence was not far from Turing's thoughts: he described himself as ‘building a brain’ and remarked in a letter that he was ‘more interested in the possibility of producing models of the action of the brain than in the practical applications to computing’.) John Womersley, Turing's immediate superior at NPL, christened Turing's proposed machine the Automatic Computing Engine, or ACE, in homage to Babbage's Difference Engine and Analytical Engine.

Turing's 1945 report ‘Proposed Electronic Calculator’ gave the first relatively complete specification of an electronic stored-program general-purpose digital computer. The report is reprinted in full in Copeland 2005.

The first electronic stored-program digital computer to be proposed in the U.S. was the EDVAC (see below). The ‘First Draft of a Report on the EDVAC’ (May 1945), composed by von Neumann, contained little engineering detail, in particular concerning electronic hardware (owing to restrictions in the U.S.). Turing's ‘Proposed Electronic Calculator’, on the other hand, supplied detailed circuit designs and specifications of hardware units, specimen programs in machine code, and even an estimate of the cost of building the machine (£11,200). ACE and EDVAC differed fundamentally from one another; for example, ACE employed distributed processing, while EDVAC had a centralised structure.

Turing saw that speed and memory were the keys to computing. Turing's colleague at NPL, Jim Wilkinson, observed that Turing ‘was obsessed with the idea of speed on the machine’ [Copeland 2005, p. 2]. Turing's design had much in common with today's RISC architectures and it called for a high-speed memory of roughly the same capacity as an early Macintosh computer (enormous by the standards of his day). Had Turing's ACE been built as planned it would have been in a different league from the other early computers. However, progress on Turing's Automatic Computing Engine ran slowly, due to organisational difficulties at NPL, and in 1948 a ‘very fed up’ Turing (Robin Gandy's description, in interview with Copeland, 1995) left NPL for Newman's Computing Machine Laboratory at Manchester University. It was not until May 1950 that a small pilot model of the Automatic Computing Engine, built by Wilkinson, Edward Newman, Mike Woodger, and others, first executed a program. With an operating speed of 1 MHz, the Pilot Model ACE was for some time the fastest computer in the world.

Sales of DEUCE, the production version of the Pilot Model ACE, were buoyant — confounding the suggestion, made in 1946 by the Director of the NPL, Sir Charles Darwin, that ‘it is very possible that … one machine would suffice to solve all the problems that are demanded of it from the whole country’ [Copeland 2005, p. 4]. The fundamentals of Turing's ACE design were employed by Harry Huskey (at Wayne State University, Detroit) in the Bendix G15 computer (Huskey in interview with Copeland, 1998). The G15 was arguably the first personal computer; over 400 were sold worldwide. DEUCE and the G15 remained in use until about 1970. Another computer deriving from Turing's ACE design, the MOSAIC, played a role in Britain's air defences during the Cold War period; other derivatives include the Packard-Bell PB250 (1961). (More information about these early computers is given in [Copeland 2005].)

The earliest general-purpose stored-program electronic digital computer to work was built in Newman's Computing Machine Laboratory at Manchester University. The Manchester ‘Baby’, as it became known, was constructed by the engineers F.C. Williams and Tom Kilburn, and performed its first calculation on 21 June 1948. The tiny program, stored on the face of a cathode ray tube, was just seventeen instructions long. A much enlarged version of the machine, with a programming system designed by Turing, became the world's first commercially available computer, the Ferranti Mark I. The first to be completed was installed at Manchester University in February 1951; in all about ten were sold, in Britain, Canada, Holland and Italy.

The fundamental logico-mathematical contributions by Turing and Newman to the triumph at Manchester have been neglected, and the Manchester machine is nowadays remembered as the work of Williams and Kilburn. Indeed, Newman's role in the development of computers has never been sufficiently emphasised (due perhaps to his thoroughly self-effacing way of relating the relevant events).

It was Newman who, in a lecture in Cambridge in 1935, introduced Turing to the concept that led directly to the Turing machine: Newman defined a constructive process as one that a machine can carry out (Newman in interview with Evans, op. cit.). As a result of his knowledge of Turing's work, Newman became interested in the possibilities of computing machinery in, as he put it, ‘a rather theoretical way’. It was not until Newman joined GC&CS in 1942 that his interest in computing machinery suddenly became practical, with his realisation that the attack on Tunny could be mechanised. During the building of Colossus, Newman tried to interest Flowers in Turing's 1936 paper — birthplace of the stored-program concept - but Flowers did not make much of Turing's arcane notation. There is no doubt that by 1943, Newman had firmly in mind the idea of using electronic technology in order to construct a stored-program general-purpose digital computing machine.

In July of 1946 (the month in which the Royal Society approved Newman's application for funds to found the Computing Machine Laboratory), Freddie Williams, working at the Telecommunications Research Establishment, Malvern, began the series of experiments on cathode ray tube storage that was to lead to the Williams tube memory. Williams, until then a radar engineer, explains how it was that he came to be working on the problem of computer memory:

[O]nce [the German Armies] collapsed … nobody was going to care a toss about radar, and people like me … were going to be in the soup unless we found something else to do. And computers were in the air. Knowing absolutely nothing about them I latched onto the problem of storage and tackled that. (Quoted in Bennett 1976.)

Newman learned of Williams' work, and with the able help of Patrick Blackett, Langworthy Professor of Physics at Manchester and one of the most powerful figures in the University, was instrumental in the appointment of the 35 year old Williams to the recently vacated Chair of Electro-Technics at Manchester. (Both were members of the appointing committee (Kilburn in interview with Copeland, 1997).) Williams immediately had Kilburn, his assistant at Malvern, seconded to Manchester. To take up the story in Williams' own words:

[N]either Tom Kilburn nor I knew the first thing about computers when we arrived in Manchester University. We'd had enough explained to us to understand what the problem of storage was and what we wanted to store, and that we'd achieved, so the point now had been reached when we'd got to find out about computers … Newman explained the whole business of how a computer works to us. (F.C. Williams in interview with Evans [1976])

Elsewhere Williams is explicit concerning Turing's role and gives something of the flavour of the explanation that he and Kilburn received:

Tom Kilburn and I knew nothing about computers, but a lot about circuits. Professor Newman and Mr A.M. Turing … knew a lot about computers and substantially nothing about electronics. They took us by the hand and explained how numbers could live in houses with addresses and how if they did they could be kept track of during a calculation. (Williams [1975], p. 328)

It seems that Newman must have used much the same words with Williams and Kilburn as he did in an address to the Royal Society on 4th March 1948:

Professor Hartree … has recalled that all the essential ideas of the general-purpose calculating machines now being made are to be found in Babbage's plans for his analytical engine. In modern times the idea of a universal calculating machine was independently introduced by Turing … [T]he machines now being made in America and in this country … [are] in certain general respects … all similar. There is provision for storing numbers, say in the scale of 2, so that each number appears as a row of, say, forty 0's and 1's in certain places or "houses" in the machine. … Certain of these numbers, or "words" are read, one after another, as orders. In one possible type of machine an order consists of four numbers, for example 11, 13, 27, 4. The number 4 signifies "add", and when control shifts to this word the "houses" H11 and H13 will be connected to the adder as inputs, and H27 as output. The numbers stored in H11 and H13 pass through the adder, are added, and the sum is passed on to H27. The control then shifts to the next order. In most real machines the process just described would be done by three separate orders, the first bringing [H11] (=content of H11) to a central accumulator, the second adding [H13] into the accumulator, and the third sending the result to H27; thus only one address would be required in each order. … A machine with storage, with this automatic-telephone-exchange arrangement and with the necessary adders, subtractors and so on, is, in a sense, already a universal machine. (Newman [1948], pp. 271–272)

Following this explanation of Turing's three-address concept (source 1, source 2, destination, function) Newman went on to describe program storage (‘the orders shall be in a series of houses X1, X2, …’) and conditional branching. He then summed up:

From this highly simplified account it emerges that the essential internal parts of the machine are, first, a storage for numbers (which may also be orders). … Secondly, adders, multipliers, etc. Thirdly, an "automatic telephone exchange" for selecting "houses", connecting them to the arithmetic organ, and writing the answers in other prescribed houses. Finally, means of moving control at any stage to any chosen order, if a certain condition is satisfied, otherwise passing to the next order in the normal sequence. Besides these there must be ways of setting up the machine at the outset, and extracting the final answer in useable form. (Newman [1948], pp. 273–4)

In a letter written in 1972 Williams described in some detail what he and Kilburn were told by Newman:

About the middle of the year [1946] the possibility of an appointment at Manchester University arose and I had a talk with Professor Newman who was already interested in the possibility of developing computers and had acquired a grant from the Royal Society of £30,000 for this purpose. Since he understood computers and I understood electronics the possibilities of fruitful collaboration were obvious. I remember Newman giving us a few lectures in which he outlined the organisation of a computer in terms of numbers being identified by the address of the house in which they were placed and in terms of numbers being transferred from this address, one at a time, to an accumulator where each entering number was added to what was already there. At any time the number in the accumulator could be transferred back to an assigned address in the store and the accumulator cleared for further use. The transfers were to be effected by a stored program in which a list of instructions was obeyed sequentially. Ordered progress through the list could be interrupted by a test instruction which examined the sign of the number in the accumulator. Thereafter operation started from a new point in the list of instructions. This was the first information I received about the organisation of computers. … Our first computer was the simplest embodiment of these principles, with the sole difference that it used a subtracting rather than an adding accumulator. (Letter from Williams to Randell, 1972; in Randell [1972], p. 9)

Turing's early input to the developments at Manchester, hinted at by Williams in his above-quoted reference to Turing, may have been via the lectures on computer design that Turing and Wilkinson gave in London during the period December 1946 to February 1947 (Turing and Wilkinson [1946–7]). The lectures were attended by representatives of various organisations planning to use or build an electronic computer. Kilburn was in the audience (Bowker and Giordano [1993]). (Kilburn usually said, when asked from where he obtained his basic knowledge of the computer, that he could not remember (letter from Brian Napper to Copeland, 2002); for example, in a 1992 interview he said: ‘Between early 1945 and early 1947, in that period, somehow or other I knew what a digital computer was … Where I got this knowledge from I've no idea’ (Bowker and Giordano [1993], p. 19).)

Whatever role Turing's lectures may have played in informing Kilburn, there is little doubt that credit for the Manchester computer — called the ‘Newman-Williams machine’ in a contemporary document (Huskey 1947) — belongs not only to Williams and Kilburn but also to Newman, and that the influence on Newman of Turing's 1936 paper was crucial, as was the influence of Flowers' Colossus.

The first working AI program, a draughts (checkers) player written by Christopher Strachey, ran on the Ferranti Mark I in the Manchester Computing Machine Laboratory. Strachey (at the time a teacher at Harrow School and an amateur programmer) wrote the program with Turing's encouragement and utilising the latter's recently completed Programmers' Handbook for the Ferranti. (Strachey later became Director of the Programming Research Group at Oxford University.) By the summer of 1952, the program could, Strachey reported, ‘play a complete game of draughts at a reasonable speed’. (Strachey's program formed the basis for Arthur Samuel's well-known checkers program.) The first chess-playing program, also, was written for the Manchester Ferranti, by Dietrich Prinz; the program first ran in November 1951. Designed for solving simple problems of the mate-in-two variety, the program would examine every possible move until a solution was found. Turing started to program his ‘Turochamp’ chess-player on the Ferranti Mark I, but never completed the task. Unlike Prinz's program, the Turochamp could play a complete game (when hand-simulated) and operated not by exhaustive search but under the guidance of heuristics.

The first fully functioning electronic digital computer to be built in the U.S. was ENIAC, constructed at the Moore School of Electrical Engineering, University of Pennsylvania, for the Army Ordnance Department, by J. Presper Eckert and John Mauchly. Completed in 1945, ENIAC was somewhat similar to the earlier Colossus, but considerably larger and more flexible (although far from general-purpose). The primary function for which ENIAC was designed was the calculation of tables used in aiming artillery. ENIAC was not a stored-program computer, and setting it up for a new job involved reconfiguring the machine by means of plugs and switches. For many years, ENIAC was believed to have been the first functioning electronic digital computer, Colossus being unknown to all but a few.

In 1944, John von Neumann joined the ENIAC group. He had become ‘intrigued’ (Goldstine's word, [1972], p. 275) with Turing's universal machine while Turing was at Princeton University during 1936–1938. At the Moore School, von Neumann emphasised the importance of the stored-program concept for electronic computing, including the possibility of allowing the machine to modify its own program in useful ways while running (for example, in order to control loops and branching). Turing's paper of 1936 (‘On Computable Numbers, with an Application to the Entscheidungsproblem’) was required reading for members of von Neumann's post-war computer project at the Institute for Advanced Study, Princeton University (letter from Julian Bigelow to Copeland, 2002; see also Copeland [2004], p. 23). Eckert appears to have realised independently, and prior to von Neumann's joining the ENIAC group, that the way to take full advantage of the speed at which data is processed by electronic circuits is to place suitably encoded instructions for controlling the processing in the same high-speed storage devices that hold the data itself (documented in Copeland [2004], pp. 26–7). In 1945, while ENIAC was still under construction, von Neumann produced a draft report, mentioned previously, setting out the ENIAC group's ideas for an electronic stored-program general-purpose digital computer, the EDVAC (von Neuman [1945]). The EDVAC was completed six years later, but not by its originators, who left the Moore School to build computers elsewhere. Lectures held at the Moore School in 1946 on the proposed EDVAC were widely attended and contributed greatly to the dissemination of the new ideas.

Von Neumann was a prestigious figure and he made the concept of a high-speed stored-program digital computer widely known through his writings and public addresses. As a result of his high profile in the field, it became customary, although historically inappropriate, to refer to electronic stored-program digital computers as ‘von Neumann machines’.

The Los Alamos physicist Stanley Frankel, responsible with von Neumann and others for mechanising the large-scale calculations involved in the design of the atomic bomb, has described von Neumann's view of the importance of Turing's 1936 paper, in a letter:

I know that in or about 1943 or ‘44 von Neumann was well aware of the fundamental importance of Turing's paper of 1936 … Von Neumann introduced me to that paper and at his urging I studied it with care. Many people have acclaimed von Neumann as the "father of the computer" (in a modern sense of the term) but I am sure that he would never have made that mistake himself. He might well be called the midwife, perhaps, but he firmly emphasized to me, and to others I am sure, that the fundamental conception is owing to Turing, in so far as not anticipated by Babbage … Both Turing and von Neumann, of course, also made substantial contributions to the "reduction to practice" of these concepts but I would not regard these as comparable in importance with the introduction and explication of the concept of a computer able to store in its memory its program of activities and of modifying that program in the course of these activities. (Quoted in Randell [1972], p. 10)

Other notable early stored-program electronic digital computers were:

• EDSAC, 1949, built at Cambridge University by Maurice Wilkes
• BINAC, 1949, built by Eckert's and Mauchly's Electronic Control Co., Philadelphia (opinions differ over whether BINAC ever actually worked)
• Whirlwind I, 1949, Digital Computer Laboratory, Massachusetts Institute of Technology, Jay Forrester
• SEAC, 1950, US Bureau of Standards Eastern Division, Washington D.C., Samuel Alexander, Ralph Slutz
• SWAC, 1950, US Bureau of Standards Western Division, Institute for Numerical Analysis, University of California at Los Angeles, Harry Huskey
• UNIVAC, 1951, Eckert-Mauchly Computer Corporation, Philadelphia (the first computer to be available commercially in the U.S.)
• the IAS computer, 1952, Institute for Advanced Study, Princeton University, Julian Bigelow, Arthur Burks, Herman Goldstine, von Neumann, and others (thanks to von Neumann's publishing the specifications of the IAS machine, it became the model for a group of computers known as the Princeton Class machines; the IAS computer was also a strong influence on the IBM 701)
• IBM 701, 1952, International Business Machine's first mass-produced electronic stored-program computer.

The EDVAC and ACE proposals both advocated the use of mercury-filled tubes, called ‘delay lines’, for high-speed internal memory. This form of memory is known as acoustic memory. Delay lines had initially been developed for echo cancellation in radar; the idea of using them as memory devices originated with Eckert at the Moore School. Here is Turing's description:

It is proposed to build "delay line" units consisting of mercury … tubes about 5′ long and 1″ in diameter in contact with a quartz crystal at each end. The velocity of sound in … mercury … is such that the delay will be 1.024 ms. The information to be stored may be considered to be a sequence of 1024 ‘digits’ (0 or 1) … These digits will be represented by a corresponding sequence of pulses. The digit 0 … will be represented by the absence of a pulse at the appropriate time, the digit 1 … by its presence. This series of pulses is impressed on the end of the line by one piezo-crystal, it is transmitted down the line in the form of supersonic waves, and is reconverted into a varying voltage by the crystal at the far end. This voltage is amplified sufficiently to give an output of the order of 10 volts peak to peak and is used to gate a standard pulse generated by the clock. This pulse may be again fed into the line by means of the transmitting crystal, or we may feed in some altogether different signal. We also have the possibility of leading the gated pulse to some other part of the calculator, if we have need of that information at the time. Making use of the information does not of course preclude keeping it also. (Turing [1945], p. 375)

Mercury delay line memory was used in EDSAC, BINAC, SEAC, Pilot Model ACE, EDVAC, DEUCE, and full-scale ACE (1958). The chief advantage of the delay line as a memory medium was, as Turing put it, that delay lines were "already a going concern" (Turing [1947], p. 380). The fundamental disadvantages of the delay line were that random access is impossible and, moreover, the time taken for an instruction, or number, to emerge from a delay line depends on where in the line it happens to be.

In order to minimize waiting-time, Turing arranged for instructions to be stored not in consecutive positions in the delay line, but in relative positions selected by the programmer in such a way that each instruction would emerge at exactly the time it was required, in so far as this was possible. Each instruction contained a specification of the location of the next. This system subsequently became known as ‘optimum coding’. It was an integral feature of every version of the ACE design. Optimum coding made for difficult and untidy programming, but the advantage in terms of speed was considerable. Thanks to optimum coding, the Pilot Model ACE was able to do a floating point multiplication in 3 milliseconds (Wilkes's EDSAC required 4.5 milliseconds to perform a single fixed point multiplication).

In the Williams tube or electrostatic memory, previously mentioned, a two-dimensional rectangular array of binary digits was stored on the face of a commercially-available cathode ray tube. Access to data was immediate. Williams tube memories were employed in the Manchester series of machines, SWAC, the IAS computer, and the IBM 701, and a modified form of Williams tube in Whirlwind I (until replacement by magnetic core in 1953).

Drum memories, in which data was stored magnetically on the surface of a metal cylinder, were developed on both sides of the Atlantic. The initial idea appears to have been Eckert's. The drum provided reasonably large quantities of medium-speed memory and was used to supplement a high-speed acoustic or electrostatic memory. In 1949, the Manchester computer was successfully equipped with a drum memory; this was constructed by the Manchester engineers on the model of a drum developed by Andrew Booth at Birkbeck College, London.

The final major event in the early history of electronic computation was the development of magnetic core memory. Jay Forrester realised that the hysteresis properties of magnetic core (normally used in transformers) lent themselves to the implementation of a three-dimensional solid array of randomly accessible storage points. In 1949, at Massachusetts Institute of Technology, he began to investigate this idea empirically. Forrester's early experiments with metallic core soon led him to develop the superior ferrite core memory. Digital Equipment Corporation undertook to build a computer similar to the Whirlwind I as a test vehicle for a ferrite core memory. The Memory Test Computer was completed in 1953. (This computer was used in 1954 for the first simulations of neural networks, by Belmont Farley and Wesley Clark of MIT's Lincoln Laboratory (see Copeland and Proudfoot [1996]).

Once the absolute reliability, relative cheapness, high capacity and permanent life of ferrite core memory became apparent, core soon replaced other forms of high-speed memory. The IBM 704 and 705 computers (announced in May and October 1954, respectively) brought core memory into wide use.

Works Cited

• Babbage, C. (ed. by Campbell-Kelly, M.), 1994, Passages from the Life of a Philosopher , New Brunswick: Rutgers University Press
• Bennett, S., 1976, ‘F.C. Williams: his contribution to the development of automatic control’, National Archive for the History of Computing, University of Manchester, England. (This is a typescript based on interviews with Williams in 1976.)
• Bowker, G., and Giordano, R., 1993, ‘Interview with Tom Kilburn’, Annals of the History of Computing , 15 : 17–32.
• Copeland, B.J. (ed.), 2004, The Essential Turing Oxford University Press
• Copeland, B.J. (ed.), 2005, Alan Turing's Automatic Computing Engine: The Master Codebreaker's Struggle to Build the Modern Computer Oxford University Press
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• Turing, A.M., and Wilkinson, J.H., 1946–7, ‘The Turing-Wilkinson Lecture Series (1946-7)’, in Alan Turing's Automatic Computing Engine (Copeland [2005])
• von Neumann, J., 1945, ‘First Draft of a Report on the EDVAC’, in Stern, N. From ENIAC to UNIVAC: An Appraisal of the Eckert-Mauchly Computers Bedford, Mass.: Digital Press (1981), pp. 181–246
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Further Reading

• Copeland, B.J., 2004, ‘Colossus — Its Origins and Originators’ Annals of the History of Computing , 26 : 38–45
• Metropolis, N., Howlett, J., Rota, G.C. (eds), 1980, A History of Computing in the Twentieth Century New York: Academic Press
• Randell, B. (ed.), 1982, The Origins of Digital Computers: Selected Papers Berlin: Springer-Verlag
• Williams, M.R., 1997, A History of Computing Technology Los Alamitos: IEEE Computer Society Press

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History of Computing

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• Joseph Migga Kizza 2  

Part of the book series: Texts in Computer Science ((TCS))

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This chapter gives an overview of the history of computing science in hardware, software, and networking, covering prehistoric (prior to 1946) computing devices and computing pioneers since the Abacus . The emergency of social and ethical problems in computing is discussed via the history of computer crimes which started with the invention of the computer virus.

We also discuss the growth of computing technologies like the Internet, the Web, and advanced mobile computing technologies and the rise of computer crimes. Finally we introduce the need for computer ethics education as one of the solutions to the growing threat of a cyberspace attack.

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A history of computers. http://www.maxmon.com/timeline.html

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Gribble C (2001) History of the web beginning at CERN. Hitmill, January 18

Kizza JM (1998) Civilizing the internet: global concerns and efforts towards regulation. McFarland, Jefferson

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Carnegie Mellon University, Software Engineering Institute. http://www.cert.org/stats/cert_stats.html#incidents

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Bynum TW (ed) (1985) Computers & ethics. Basil Blackwell, New York

Maner W (1996) Is computer ethics unique? Sci Eng Ethics 2(2):137–154. See http://www.cableol.co.uk/opragen/

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Kizza, J.M. (2013). History of Computing. In: Ethical and Social Issues in the Information Age. Texts in Computer Science. Springer, London. https://doi.org/10.1007/978-1-4471-4990-3_1

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Bell Laboratories scientist George Stibitz uses relays for a demonstration adder

“Model K” Adder

Called the “Model K” Adder because he built it on his “Kitchen” table, this simple demonstration circuit provides proof of concept for applying Boolean logic to the design of computers, resulting in construction of the relay-based Model I Complex Calculator in 1939. That same year in Germany, engineer Konrad Zuse built his Z2 computer, also using telephone company relays.

Hewlett-Packard is founded

Hewlett and Packard in their garage workshop

David Packard and Bill Hewlett found their company in a Palo Alto, California garage. Their first product, the HP 200A Audio Oscillator, rapidly became a popular piece of test equipment for engineers. Walt Disney Pictures ordered eight of the 200B model to test recording equipment and speaker systems for the 12 specially equipped theatres that showed the movie “Fantasia” in 1940.

The Complex Number Calculator (CNC) is completed

Operator at Complex Number Calculator (CNC)

In 1939, Bell Telephone Laboratories completes this calculator, designed by scientist George Stibitz. In 1940, Stibitz demonstrated the CNC at an American Mathematical Society conference held at Dartmouth College. Stibitz stunned the group by performing calculations remotely on the CNC (located in New York City) using a Teletype terminal connected to New York over special telephone lines. This is likely the first example of remote access computing.

Konrad Zuse finishes the Z3 Computer

The Zuse Z3 Computer

The Z3, an early computer built by German engineer Konrad Zuse working in complete isolation from developments elsewhere, uses 2,300 relays, performs floating point binary arithmetic, and has a 22-bit word length. The Z3 was used for aerodynamic calculations but was destroyed in a bombing raid on Berlin in late 1943. Zuse later supervised a reconstruction of the Z3 in the 1960s, which is currently on display at the Deutsches Museum in Munich.

The first Bombe is completed

Bombe replica, Bletchley Park, UK

Built as an electro-mechanical means of decrypting Nazi ENIGMA-based military communications during World War II, the British Bombe is conceived of by computer pioneer Alan Turing and Harold Keen of the British Tabulating Machine Company. Hundreds of allied bombes were built in order to determine the daily rotor start positions of Enigma cipher machines, which in turn allowed the Allies to decrypt German messages. The basic idea for bombes came from Polish code-breaker Marian Rejewski's 1938 "Bomba."

The Atanasoff-Berry Computer (ABC) is completed

The Atanasoff-Berry Computer

After successfully demonstrating a proof-of-concept prototype in 1939, Professor John Vincent Atanasoff receives funds to build a full-scale machine at Iowa State College (now University). The machine was designed and built by Atanasoff and graduate student Clifford Berry between 1939 and 1942. The ABC was at the center of a patent dispute related to the invention of the computer, which was resolved in 1973 when it was shown that ENIAC co-designer John Mauchly had seen the ABC shortly after it became functional.

The legal result was a landmark: Atanasoff was declared the originator of several basic computer ideas, but the computer as a concept was declared un-patentable and thus freely open to all. A full-scale working replica of the ABC was completed in 1997, proving that the ABC machine functioned as Atanasoff had claimed. The replica is currently on display at the Computer History Museum.

Bell Labs Relay Interpolator is completed

George Stibitz circa 1940

The US Army asked Bell Laboratories to design a machine to assist in testing its M-9 gun director, a type of analog computer that aims large guns to their targets. Mathematician George Stibitz recommends using a relay-based calculator for the project. The result was the Relay Interpolator, later called the Bell Labs Model II. The Relay Interpolator used 440 relays, and since it was programmable by paper tape, was used for other applications following the war.

Curt Herzstark designs Curta calculator

Curta Model 1 calculator

Curt Herzstark was an Austrian engineer who worked in his family’s manufacturing business until he was arrested by the Nazis in 1943. While imprisoned at Buchenwald concentration camp for the rest of World War II, he refines his pre-war design of a calculator featuring a modified version of Leibniz’s “stepped drum” design. After the war, Herzstark’s Curta made history as the smallest all-mechanical, four-function calculator ever built.

First Colossus operational at Bletchley Park

The Colossus at work at Bletchley Park

Designed by British engineer Tommy Flowers, the Colossus is designed to break the complex Lorenz ciphers used by the Nazis during World War II. A total of ten Colossi were delivered, each using as many as 2,500 vacuum tubes. A series of pulleys transported continuous rolls of punched paper tape containing possible solutions to a particular code. Colossus reduced the time to break Lorenz messages from weeks to hours. Most historians believe that the use of Colossus machines significantly shortened the war by providing evidence of enemy intentions and beliefs. The machine’s existence was not made public until the 1970s.

Harvard Mark 1 is completed

Conceived by Harvard physics professor Howard Aiken, and designed and built by IBM, the Harvard Mark 1 is a room-sized, relay-based calculator. The machine had a fifty-foot long camshaft running the length of machine that synchronized the machine’s thousands of component parts and used 3,500 relays. The Mark 1 produced mathematical tables but was soon superseded by electronic stored-program computers.

John von Neumann writes First Draft of a Report on the EDVAC

John von Neumann

In a widely circulated paper, mathematician John von Neumann outlines the architecture of a stored-program computer, including electronic storage of programming information and data -- which eliminates the need for more clumsy methods of programming such as plugboards, punched cards and paper. Hungarian-born von Neumann demonstrated prodigious expertise in hydrodynamics, ballistics, meteorology, game theory, statistics, and the use of mechanical devices for computation. After the war, he concentrated on the development of Princeton´s Institute for Advanced Studies computer.

Moore School lectures take place

The Moore School Building at the University of Pennsylvania

An inspiring summer school on computing at the University of Pennsylvania´s Moore School of Electrical Engineering stimulates construction of stored-program computers at universities and research institutions in the US, France, the UK, and Germany. Among the lecturers were early computer designers like John von Neumann, Howard Aiken, J. Presper Eckert and John Mauchly, as well as mathematicians including Derrick Lehmer, George Stibitz, and Douglas Hartree. Students included future computing pioneers such as Maurice Wilkes, Claude Shannon, David Rees, and Jay Forrester. This free, public set of lectures inspired the EDSAC, BINAC, and, later, IAS machine clones like the AVIDAC.

Project Whirlwind begins

Whirlwind installation at MIT

During World War II, the US Navy approaches the Massachusetts Institute of Technology (MIT) about building a flight simulator to train bomber crews. Under the leadership of MIT's Gordon Brown and Jay Forrester, the team first built a small analog simulator, but found it inaccurate and inflexible. News of the groundbreaking electronic ENIAC computer that same year inspired the group to change course and attempt a digital solution, whereby flight variables could be rapidly programmed in software. Completed in 1951, Whirlwind remains one of the most important computer projects in the history of computing. Foremost among its developments was Forrester’s perfection of magnetic core memory, which became the dominant form of high-speed random access memory for computers until the mid-1970s.

Public unveiling of ENIAC

Started in 1943, the ENIAC computing system was built by John Mauchly and J. Presper Eckert at the Moore School of Electrical Engineering of the University of Pennsylvania. Because of its electronic, as opposed to electromechanical, technology, it is over 1,000 times faster than any previous computer. ENIAC used panel-to-panel wiring and switches for programming, occupied more than 1,000 square feet, used about 18,000 vacuum tubes and weighed 30 tons. It was believed that ENIAC had done more calculation over the ten years it was in operation than all of humanity had until that time.

First Computer Program to Run on a Computer

Kilburn (left) and Williams in front of 'Baby'

University of Manchester researchers Frederic Williams, Tom Kilburn, and Geoff Toothill develop the Small-Scale Experimental Machine (SSEM), better known as the Manchester "Baby." The Baby was built to test a new memory technology developed by Williams and Kilburn -- soon known as the Williams Tube – which was the first high-speed electronic random access memory for computers. Their first program, consisting of seventeen instructions and written by Kilburn, ran on June 21st, 1948. This was the first program in history to run on a digital, electronic, stored-program computer.

SSEC goes on display

IBM Selective Sequence Electronic Calculator (SSEC)

The Selective Sequence Electronic Calculator (SSEC) project, led by IBM engineer Wallace Eckert, uses both relays and vacuum tubes to process scientific data at the rate of 50 14 x 14 digit multiplications per second. Before its decommissioning in 1952, the SSEC produced the moon position tables used in early planning of the 1969 Apollo XII moon landing. These tables were later confirmed by using more modern computers for the actual flights. The SSEC was one of the last of the generation of 'super calculators' to be built using electromechanical technology.

CSIRAC runs first program

While many early digital computers were based on similar designs, such as the IAS and its copies, others are unique designs, like the CSIRAC. Built in Sydney, Australia by the Council of Scientific and Industrial Research for use in its Radio physics Laboratory in Sydney, CSIRAC was designed by British-born Trevor Pearcey, and used unusual 12-hole paper tape. It was transferred to the Department of Physics at the University of Melbourne in 1955 and remained in service until 1964.

EDSAC completed

The first practical stored-program computer to provide a regular computing service, EDSAC is built at Cambridge University using vacuum tubes and mercury delay lines for memory. The EDSAC project was led by Cambridge professor and director of the Cambridge Computation Laboratory, Maurice Wilkes. Wilkes' ideas grew out of the Moore School lectures he had attended three years earlier. One major advance in programming was Wilkes' use of a library of short programs, called “subroutines,” stored on punched paper tapes and used for performing common repetitive calculations within a larger program.

MADDIDA developed

MADDIDA (Magnetic Drum Digital Differential Analyzer) prototype

MADDIDA is a digital drum-based differential analyzer. This type of computer is useful in performing many of the mathematical equations scientists and engineers encounter in their work. It was originally created for a nuclear missile design project in 1949 by a team led by Fred Steele. It used 53 vacuum tubes and hundreds of germanium diodes, with a magnetic drum for memory. Tracks on the drum did the mathematical integration. MADDIDA was flown across the country for a demonstration to John von Neumann, who was impressed. Northrop was initially reluctant to make MADDIDA a commercial product, but by the end of 1952, six had sold.

Manchester Mark I completed

Manchester Mark I

Built by a team led by engineers Frederick Williams and Tom Kilburn, the Mark I serves as the prototype for Ferranti’s first computer – the Ferranti Mark 1. The Manchester Mark I used more than 1,300 vacuum tubes and occupied an area the size of a medium room. Its “Williams-Kilburn tube” memory system was later adopted by several other early computer systems around the world.

ERA 1101 introduced

One of the first commercially produced computers, the company´s first customer was the US Navy. The 1101, designed by ERA but built by Remington-Rand, was intended for high-speed computing and stored 1 million bits on its magnetic drum, one of the earliest magnetic storage devices and a technology which ERA had done much to perfect in its own laboratories. Many of the 1101’s basic architectural details were used again in later Remington-Rand computers until the 1960s.

NPL Pilot ACE completed

Based on ideas from Alan Turing, Britain´s Pilot ACE computer is constructed at the National Physical Laboratory. "We are trying to build a machine to do all kinds of different things simply by programming rather than by the addition of extra apparatus," Turing said at a symposium on large-scale digital calculating machinery in 1947 in Cambridge, Massachusetts. The design packed 800 vacuum tubes into a relatively compact 12 square feet.

Plans to build the Simon 1 relay logic machine are published

Simon featured on the November 1950 Scientific American cover

The hobbyist magazine Radio Electronics publishes Edmund Berkeley's design for the Simon 1 relay computer from 1950 to 1951. The Simon 1 used relay logic and cost about $600 to build. In his book Giant Brains , Berkeley noted - “We shall now consider how we can design a very simple machine that will think. Let us call it Simon, because of its predecessor, Simple Simon... Simon is so simple and so small in fact that it could be built to fill up less space than a grocery-store box; about four cubic feet.”

SEAC and SWAC completed

The Standards Eastern Automatic Computer (SEAC) is among the first stored program computers completed in the United States. It was built in Washington DC as a test-bed for evaluating components and systems as well as for setting computer standards. It was also one of the first computers to use all-diode logic, a technology more reliable than vacuum tubes. The world's first scanned image was made on SEAC by engineer Russell Kirsch in 1957.

The NBS also built the Standards Western Automatic Computer (SWAC) at the Institute for Numerical Analysis on the UCLA campus. Rather than testing components like the SEAC, the SWAC was built using already-developed technology. SWAC was used to solve problems in numerical analysis, including developing climate models and discovering five previously unknown Mersenne prime numbers.

Ferranti Mark I sold

Ferranti Mark 1

The title of “first commercially available general-purpose computer” probably goes to Britain’s Ferranti Mark I for its sale of its first Mark I computer to Manchester University. The Mark 1 was a refinement of the experimental Manchester “Baby” and Manchester Mark 1 computers, also at Manchester University. A British government contract spurred its initial development but a change in government led to loss of funding and the second and only other Mark I was sold at a major loss to the University of Toronto, where it was re-christened FERUT.

First Univac 1 delivered to US Census Bureau

Univac 1 installation

The Univac 1 is the first commercial computer to attract widespread public attention. Although manufactured by Remington Rand, the machine was often mistakenly referred to as “the IBM Univac." Univac computers were used in many different applications but utilities, insurance companies and the US military were major customers. One biblical scholar even used a Univac 1 to compile a concordance to the King James version of the Bible. Created by Presper Eckert and John Mauchly -- designers of the earlier ENIAC computer -- the Univac 1 used 5,200 vacuum tubes and weighed 29,000 pounds. Remington Rand eventually sold 46 Univac 1s at more than $1 million each.

J. Lyons & Company introduce LEO-1

Modeled after the Cambridge University EDSAC computer, the president of Lyons Tea Co. has the LEO built to solve the problem of production scheduling and delivery of cakes to the hundreds of Lyons tea shops around England. After the success of the first LEO, Lyons went into business manufacturing computers to meet the growing need for data processing systems in business. The LEO was England’s first commercial computer and was performing useful work before any other commercial computer system in the world.

IAS computer operational

MANIAC at Los Alamos

The Institute of Advanced Study (IAS) computer is a multi-year research project conducted under the overall supervision of world-famous mathematician John von Neumann. The notion of storing both data and instructions in memory became known as the ‘stored program concept’ to distinguish it from earlier methods of instructing a computer. The IAS computer was designed for scientific calculations and it performed essential work for the US atomic weapons program. Over the next few years, the basic design of the IAS machine was copied in at least 17 places and given similar-sounding names, for example, the MANIAC at Los Alamos Scientific Laboratory; the ILLIAC at the University of Illinois; the Johnniac at The Rand Corporation; and the SILLIAC in Australia.

Grimsdale and Webb build early transistorized computer

Manchester transistorized computer

Working under Tom Kilburn at England’s Manchester University, Richard Grimsdale and Douglas Webb demonstrate a prototype transistorized computer, the "Manchester TC", on November 16, 1953. The 48-bit machine used 92 point-contact transistors and 550 diodes.

IBM ships its Model 701 Electronic Data Processing Machine

Cuthbert Hurd (standing) and Thomas Watson, Sr. at IBM 701 console

During three years of production, IBM sells 19 701s to research laboratories, aircraft companies, and the federal government. Also known inside IBM as the “Defense Calculator," the 701 rented for $15,000 a month. Programmer Arthur Samuels used the 701 to write the first computer program designed to play checkers. The 701 introduction also marked the beginning of IBM’s entry into the large-scale computer market, a market it came to dominate in later decades.

RAND Corporation completes Johnniac computer

RAND Corporation’s Johnniac

The Johnniac computer is one of 17 computers that followed the basic design of Princeton's Institute of Advanced Study (IAS) computer. It was named after John von Neumann, a world famous mathematician and computer pioneer of the day. Johnniac was used for scientific and engineering calculations. It was also repeatedly expanded and improved throughout its 13-year lifespan. Many innovative programs were created for Johnniac, including the time-sharing system JOSS that allowed many users to simultaneously access the machine.

IBM 650 magnetic drum calculator introduced

IBM establishes the 650 as its first mass-produced computer, with the company selling 450 in just one year. Spinning at 12,500 rpm, the 650´s magnetic data-storage drum allowed much faster access to stored information than other drum-based machines. The Model 650 was also highly popular in universities, where a generation of students first learned programming.

English Electric DEUCE introduced

English Electric DEUCE

A commercial version of Alan Turing's Pilot ACE, called DEUCE—the Digital Electronic Universal Computing Engine -- is used mostly for science and engineering problems and a few commercial applications. Over 30 were completed, including one delivered to Australia.

Direct keyboard input to computers

Joe Thompson at Whirlwind console, ca. 1951

At MIT, researchers begin experimenting with direct keyboard input to computers, a precursor to today´s normal mode of operation. Typically, computer users of the time fed their programs into a computer using punched cards or paper tape. Doug Ross wrote a memo advocating direct access in February. Ross contended that a Flexowriter -- an electrically-controlled typewriter -- connected to an MIT computer could function as a keyboard input device due to its low cost and flexibility. An experiment conducted five months later on the MIT Whirlwind computer confirmed how useful and convenient a keyboard input device could be.

Librascope LGP-30 introduced

Physicist Stan Frankel, intrigued by small, general-purpose computers, developed the MINAC at Caltech. The Librascope division of defense contractor General Precision buys Frankel’s design, renaming it the LGP-30 in 1956. Used for science and engineering as well as simple data processing, the LGP-30 was a “bargain” at less than $50,000 and an early example of a ‘personal computer,’ that is, a computer made for a single user.

MIT researchers build the TX-0

TX-0 at MIT

The TX-0 (“Transistor eXperimental - 0”) is the first general-purpose programmable computer built with transistors. For easy replacement, designers placed each transistor circuit inside a "bottle," similar to a vacuum tube. Constructed at MIT´s Lincoln Laboratory, the TX-0 moved to the MIT Research Laboratory of Electronics, where it hosted some early imaginative tests of programming, including writing a Western movie shown on television, 3-D tic-tac-toe, and a maze in which a mouse found martinis and became increasingly inebriated.

Digital Equipment Corporation (DEC) founded

The Maynard mill

DEC is founded initially to make electronic modules for test, measurement, prototyping and control markets. Its founders were Ken and Stan Olsen, and Harlan Anderson. Headquartered in Maynard, Massachusetts, Digital Equipment Corporation, took over 8,680 square foot leased space in a nineteenth century mill that once produced blankets and uniforms for soldiers who fought in the Civil War. General Georges Doriot and his pioneering venture capital firm, American Research and Development, invested $70,000 for 70% of DEC’s stock to launch the company in 1957. The mill is still in use today as an office park (Clock Tower Place) today.

RCA introduces its Model 501 transistorized computer

RCA 501 brochure cover

The 501 is built on a 'building block' concept which allows it to be highly flexible for many different uses and could simultaneously control up to 63 tape drives—very useful for large databases of information. For many business users, quick access to this huge storage capability outweighed its relatively slow processing speed. Customers included US military as well as industry.

SAGE system goes online

SAGE Operator Station

The first large-scale computer communications network, SAGE connects 23 hardened computer sites in the US and Canada. Its task was to detect incoming Soviet bombers and direct interceptor aircraft to destroy them. Operators directed actions by touching a light gun to the SAGE airspace display. The air defense system used two AN/FSQ-7 computers, each of which used a full megawatt of power to drive its 55,000 vacuum tubes, 175,000 diodes and 13,000 transistors.

DEC PDP-1 introduced

Ed Fredkin at DEC PDP-1

The typical PDP-1 computer system, which sells for about $120,000, includes a cathode ray tube graphic display, paper tape input/output, needs no air conditioning and requires only one operator; all of which become standards for minicomputers. Its large scope intrigued early hackers at MIT, who wrote the first computerized video game, SpaceWar! , as well as programs to play music. More than 50 PDP-1s were sold.

NEAC 2203 goes online

NEAC 2203 transistorized computer

An early transistorized computer, the NEAC (Nippon Electric Automatic Computer) includes a CPU, console, paper tape reader and punch, printer and magnetic tape units. It was sold exclusively in Japan, but could process alphabetic and Japanese kana characters. Only about thirty NEACs were sold. It managed Japan's first on-line, real-time reservation system for Kinki Nippon Railways in 1960. The last one was decommissioned in 1979.

IBM 7030 (“Stretch”) completed

IBM Stretch

IBM´s 7000 series of mainframe computers are the company´s first to use transistors. At the top of the line was the Model 7030, also known as "Stretch." Nine of the computers, which featured dozens of advanced design innovations, were sold, mainly to national laboratories and major scientific users. A special version, known as HARVEST, was developed for the US National Security Agency (NSA). The knowledge and technologies developed for the Stretch project played a major role in the design, management, and manufacture of the later IBM System/360--the most successful computer family in IBM history.

IBM Introduces 1400 series

The 1401 mainframe, the first in the series, replaces earlier vacuum tube technology with smaller, more reliable transistors. Demand called for more than 12,000 of the 1401 computers, and the machine´s success made a strong case for using general-purpose computers rather than specialized systems. By the mid-1960s, nearly half of all computers in the world were IBM 1401s.

Minuteman I missile guidance computer developed

Minuteman Guidance computer

Minuteman missiles use transistorized computers to continuously calculate their position in flight. The computer had to be rugged and fast, with advanced circuit design and reliable packaging able to withstand the forces of a missile launch. The military’s high standards for its transistors pushed manufacturers to improve quality control. When the Minuteman I was decommissioned, some universities received these computers for use by students.

Naval Tactical Data System introduced

Naval Tactical Data System (NTDS)

The US Navy Tactical Data System uses computers to integrate and display shipboard radar, sonar and communications data. This real-time information system began operating in the early 1960s. In October 1961, the Navy tested the NTDS on the USS Oriskany carrier and the USS King and USS Mahan frigates. After being successfully used for decades, NTDS was phased out in favor of the newer AEGIS system in the 1980s.

MIT LINC introduced

Wesley Clark with LINC

The LINC is an early and important example of a ‘personal computer,’ that is, a computer designed for only one user. It was designed by MIT Lincoln Laboratory engineer Wesley Clark. Under the auspices of a National Institutes of Health (NIH) grant, biomedical research faculty from around the United States came to a workshop at MIT to build their own LINCs, and then bring them back to their home institutions where they would be used. For research, Digital Equipment Corporation (DEC) supplied the components, and 50 original LINCs were made. The LINC was later commercialized by DEC and sold as the LINC-8.

The Atlas Computer debuts

Chilton Atlas installation

A joint project of England’s Manchester University, Ferranti Computers, and Plessey, Atlas comes online nine years after Manchester’s computer lab begins exploring transistor technology. Atlas was the fastest computer in the world at the time and introduced the concept of “virtual memory,” that is, using a disk or drum as an extension of main memory. System control was provided through the Atlas Supervisor, which some consider to be the first true operating system.

CDC 6600 supercomputer introduced

The Control Data Corporation (CDC) 6600 performs up to 3 million instructions per second —three times faster than that of its closest competitor, the IBM 7030 supercomputer. The 6600 retained the distinction of being the fastest computer in the world until surpassed by its successor, the CDC 7600, in 1968. Part of the speed came from the computer´s design, which used 10 small computers, known as peripheral processing units, to offload the workload from the central processor.

Digital Equipment Corporation introduces the PDP-8

PDP-8 advertisement

The Canadian Chalk River Nuclear Lab needed a special device to monitor a reactor. Instead of designing a custom controller, two young engineers from Digital Equipment Corporation (DEC) -- Gordon Bell and Edson de Castro -- do something unusual: they develop a small, general purpose computer and program it to do the job. A later version of that machine became the PDP-8, the first commercially successful minicomputer. The PDP-8 sold for $18,000, one-fifth the price of a small IBM System/360 mainframe. Because of its speed, small size, and reasonable cost, the PDP-8 was sold by the thousands to manufacturing plants, small businesses, and scientific laboratories around the world.

IBM announces System/360

IBM 360 Model 40

System/360 is a major event in the history of computing. On April 7, IBM announced five models of System/360, spanning a 50-to-1 performance range. At the same press conference, IBM also announced 40 completely new peripherals for the new family. System/360 was aimed at both business and scientific customers and all models could run the same software, largely without modification. IBM’s initial investment of $5 billion was quickly returned as orders for the system climbed to 1,000 per month within two years. At the time IBM released the System/360, the company had just made the transition from discrete transistors to integrated circuits, and its major source of revenue began to move from punched card equipment to electronic computer systems.

SABRE comes on-line

Airline reservation agents working with SABRE

SABRE is a joint project between American Airlines and IBM. Operational by 1964, it was not the first computerized reservation system, but it was well publicized and became very influential. Running on dual IBM 7090 mainframe computer systems, SABRE was inspired by IBM’s earlier work on the SAGE air-defense system. Eventually, SABRE expanded, even making airline reservations available via on-line services such as CompuServe, Genie, and America Online.

Teletype introduced its ASR-33 Teletype

Student using ASR-33

At a cost to computer makers of roughly $700, the ASR-33 Teletype is originally designed as a low cost terminal for the Western Union communications network. Throughout the 1960s and ‘70s, the ASR-33 was a popular and inexpensive choice of input and output device for minicomputers and many of the first generation of microcomputers.

3C DDP-116 introduced

DDP-116 General Purpose Computer

Designed by engineer Gardner Hendrie for Computer Control Corporation (CCC), the DDP-116 is announced at the 1965 Spring Joint Computer Conference. It was the world's first commercial 16-bit minicomputer and 172 systems were sold. The basic computer cost $28,500.

Olivetti Programma 101 is released

Olivetti Programma 101

Announced the year previously at the New York World's Fair the Programma 101 goes on sale. This printing programmable calculator was made from discrete transistors and an acoustic delay-line memory. The Programma 101 could do addition, subtraction, multiplication, and division, as well as calculate square roots. 40,000 were sold, including 10 to NASA for use on the Apollo space project.

HP introduces the HP 2116A

HP 2116A system

The 2116A is HP’s first computer. It was developed as a versatile instrument controller for HP's growing family of programmable test and measurement products. It interfaced with a wide number of standard laboratory instruments, allowing customers to computerize their instrument systems. The 2116A also marked HP's first use of integrated circuits in a commercial product.

ILLIAC IV project begins

A large parallel processing computer, the ILLIAC IV does not operate until 1972. It was eventually housed at NASA´s Ames Research Center in Mountain View, California. The most ambitious massively parallel computer at the time, the ILLIAC IV was plagued with design and production problems. Once finally completed, it achieved a computational speed of 200 million instructions per second and 1 billion bits per second of I/O transfer via a unique combination of its parallel architecture and the overlapping or "pipelining" structure of its 64 processing elements.

RCA announces its Spectra series of computers

Image from RCA Spectra-70 brochure

The first large commercial computers to use integrated circuits, RCA highlights the IC's advantage over IBM’s custom SLT modules. Spectra systems were marketed on the basis of their compatibility with the IBM System/360 series of computer since it implemented the IBM 360 instruction set and could run most IBM software with little or no modification.

Apollo Guidance Computer (AGC) makes its debut

DSKY interface for the Apollo Guidance Computer

Designed by scientists and engineers at MIT’s Instrumentation Laboratory, the Apollo Guidance Computer (AGC) is the culmination of years of work to reduce the size of the Apollo spacecraft computer from the size of seven refrigerators side-by-side to a compact unit weighing only 70 lbs. and taking up a volume of less than 1 cubic foot. The AGC’s first flight was on Apollo 7. A year later, it steered Apollo 11 to the lunar surface. Astronauts communicated with the computer by punching two-digit codes into the display and keyboard unit (DSKY). The AGC was one of the earliest uses of integrated circuits, and used core memory, as well as read-only magnetic rope memory. The astronauts were responsible for entering more than 10,000 commands into the AGC for each trip between Earth and the Moon.

Data General Corporation introduces the Nova Minicomputer

Edson deCastro with a Data General Nova

Started by a group of engineers that left Digital Equipment Corporation (DEC), Data General designs the Nova minicomputer. It had 32 KB of memory and sold for $8,000. Ed de Castro, its main designer and co-founder of Data General, had earlier led the team that created the DEC PDP-8. The Nova line of computers continued through the 1970s, and influenced later systems like the Xerox Alto and Apple 1.

Amdahl Corporation introduces the Amdahl 470

Gene Amdahl with 470V/6 model

Gene Amdahl, father of the IBM System/360, starts his own company, Amdahl Corporation, to compete with IBM in mainframe computer systems. The 470V/6 was the company’s first product and ran the same software as IBM System/370 computers but cost less and was smaller and faster.

First Kenbak-1 is sold

One of the earliest personal computers, the Kenbak-1 is advertised for $750 in Scientific American magazine. Designed by John V. Blankenbaker using standard medium-- and small-scale integrated circuits, the Kenbak-1 relied on switches for input and lights for output from its 256-byte memory. In 1973, after selling only 40 machines, Kenbak Corporation closed its doors.

Hewlett-Packard introduces the HP-35

HP-35 handheld calculator

Initially designed for internal use by HP employees, co-founder Bill Hewlett issues a challenge to his engineers in 1971: fit all of the features of their desktop scientific calculator into a package small enough for his shirt pocket. They did. Marketed as “a fast, extremely accurate electronic slide rule” with a solid-state memory similar to that of a computer, the HP-35 distinguished itself from its competitors by its ability to perform a broad variety of logarithmic and trigonometric functions, to store more intermediate solutions for later use, and to accept and display entries in a form similar to standard scientific notation. The HP-35 helped HP become one of the most dominant companies in the handheld calculator market for more than two decades.

Intel introduces the first microprocessor

Advertisement for Intel's 4004

Computer History Museum

The first advertisement for a microprocessor, the Intel 4004, appears in Electronic News. Developed for Busicom, a Japanese calculator maker, the 4004 had 2250 transistors and could perform up to 90,000 operations per second in four-bit chunks. Federico Faggin led the design and Ted Hoff led the architecture.

Laser printer invented at Xerox PARC

Dover laser printer

Xerox PARC physicist Gary Starkweather realizes in 1967 that exposing a copy machine’s light-sensitive drum to a paper original isn’t the only way to create an image. A computer could “write” it with a laser instead. Xerox wasn’t interested. So in 1971, Starkweather transferred to Xerox Palo Alto Research Center (PARC), away from corporate oversight. Within a year, he had built the world’s first laser printer, launching a new era in computer printing, generating billions of dollars in revenue for Xerox. The laser printer was used with PARC’s Alto computer, and was commercialized as the Xerox 9700.

IBM SCAMP is developed

Dr. Paul Friedl with SCAMP prototype

Under the direction of engineer Dr. Paul Friedl, the Special Computer APL Machine Portable (SCAMP) personal computer prototype is developed at IBM's Los Gatos and Palo Alto, California laboratories. IBM’s first personal computer, the system was designed to run the APL programming language in a compact, briefcase-like enclosure which comprised a keyboard, CRT display, and cassette tape storage. Friedl used the SCAMP prototype to gain approval within IBM to promote and develop IBM’s 5100 family of computers, including the most successful, the 5150, also known as the IBM Personal Computer (PC), introduced in 1981. From concept to finished system, SCAMP took only six months to develop.

Micral is released

Based on the Intel 8008 microprocessor, the Micral is one of the earliest commercial, non-kit personal computers. Designer Thi Truong developed the computer while Philippe Kahn wrote the software. Truong, founder and president of the French company R2E, created the Micral as a replacement for minicomputers in situations that did not require high performance, such as process control and highway toll collection. Selling for $1,750, the Micral never penetrated the U.S. market. In 1979, Truong sold R2E to Bull.

The TV Typewriter plans are published

TV Typewriter

Designed by Don Lancaster, the TV Typewriter is an easy-to-build kit that can display alphanumeric information on an ordinary television set. It used $120 worth of electronics components, as outlined in the September 1973 issue of hobbyist magazine Radio Electronics . The original design included two memory boards and could generate and store 512 characters as 16 lines of 32 characters. A cassette tape interface provided supplementary storage for text. The TV Typewriter was used by many small television stations well in the 1990s.

Wang Laboratories releases the Wang 2200

Wang was a successful calculator manufacturer, then a successful word processor company. The 1973 Wang 2200 makes it a successful computer company, too. Wang sold the 2200 primarily through Value Added Resellers, who added special software to solve specific customer problems. The 2200 used a built-in CRT, cassette tape for storage, and ran the programming language BASIC. The PC era ended Wang’s success, and it filed for bankruptcy in 1992.

Scelbi advertises its 8H computer

The first commercially advertised US computer based on a microprocessor (the Intel 8008,) the Scelbi has 4 KB of internal memory and a cassette tape interface, as well as Teletype and oscilloscope interfaces. Scelbi aimed the 8H, available both in kit form and fully assembled, at scientific, electronic, and biological applications. In 1975, Scelbi introduced the 8B version with 16 KB of memory for the business market. The company sold about 200 machines, losing $500 per unit.

The Mark-8 appears in the pages of Radio-Electronics

Mark-8 featured on Radio-Electronics July 1974 cover

The Mark-8 “Do-It-Yourself” kit is designed by graduate student John Titus and uses the Intel 8008 microprocessor. The kit was the cover story of hobbyist magazine Radio-Electronics in July 1974 – six months before the MITS Altair 8800 was in rival Popular Electronics magazine. Plans for the Mark-8 cost $5 and the blank circuit boards were available for $50.

Xerox PARC Alto introduced

The Alto is a groundbreaking computer with wide influence on the computer industry. It was based on a graphical user interface using windows, icons, and a mouse, and worked together with other Altos over a local area network. It could also share files and print out documents on an advanced Xerox laser printer. Applications were also highly innovative: a WYSIWYG word processor known as “Bravo,” a paint program, a graphics editor, and email for example. Apple’s inspiration for the Lisa and Macintosh computers came from the Xerox Alto.

MITS Altair 8800 kit appears in Popular Electronics

Altair 8800

For its January issue, hobbyist magazine Popular Electronics runs a cover story of a new computer kit – the Altair 8800. Within weeks of its appearance, customers inundated its maker, MITS, with orders. Bill Gates and Paul Allen licensed their BASIC programming language interpreter to MITS as the main language for the Altair. MITS co-founder Ed Roberts invented the Altair 8800 — which sold for $297, or $395 with a case — and coined the term “personal computer”. The machine came with 256 bytes of memory (expandable to 64 KB) and an open 100-line bus structure that evolved into the “S-100” standard widely used in hobbyist and personal computers of this era. In 1977, MITS was sold to Pertec, which continued producing Altairs in 1978.

MOS 6502 is introduced

MOS 6502 ad from IEEE Computer, Sept. 1975

Chuck Peddle leads a small team of former Motorola employees to build a low-cost microprocessor. The MOS 6502 was introduced at a conference in San Francisco at a cost of $25, far less than comparable processors from Intel and Motorola, leading some attendees to believe that the company was perpetrating a hoax. The chip quickly became popular with designers of early personal computers like the Apple II and Commodore PET, as well as game consoles like the Nintendo Entertainment System. The 6502 and its progeny are still used today, usually in embedded applications.

Southwest Technical Products introduces the SWTPC 6800

Southwest Technical Products 6800

Southwest Technical Products is founded by Daniel Meyer as DEMCO in the 1960s to provide a source for kit versions of projects published in electronics hobbyist magazines. SWTPC introduces many computer kits based on the Motorola 6800, and later, the 6809. Of the dozens of different SWTP kits available, the 6800 proved the most popular.

Tandem Computers releases the Tandem-16

Dual-processor Tandem 16 system

Tailored for online transaction processing, the Tandem-16 is one of the first commercial fault-tolerant computers. The banking industry rushed to adopt the machine, built to run during repair or expansion. The Tandem-16 eventually led to the “Non-Stop” series of systems, which were used for early ATMs and to monitor stock trades.

The Video Display Module (VDM-1)

The Video Display Module (VDM)

Designed by computer pioneer Lee Felsenstein, the Video Display Module (VDM-1) marks the earliest implementation of a memory-mapped alphanumeric video display for personal computers. Introduced at the Altair Convention in Albuquerque in March 1976, it was a much-needed input device for hobbyists building their own microcomputer systems at the time and became the basis of the SOL-20 computer.

Cray-1 supercomputer introduced

Cray I 'Self-portrait'

The fastest machine of its day, The Cray-1's speed comes partly from its shape, a "C," which reduces the length of wires and thus the time signals need to travel across them. High packaging density of integrated circuits and a novel Freon cooling system also contributed to its speed. Each Cray-1 took a full year to assemble and test and cost about $10 million. Typical applications included US national defense work, including the design and simulation of nuclear weapons, and weather forecasting.

Intel 8080 and Zilog Z-80

Zilgo Z-80 microprocessor

Image by Gennadiy Shvets

Intel and Zilog introduced new microprocessors. Five times faster than its predecessor, the 8008, the Intel 8080 could address four times as many bytes for a total of 64 kilobytes. The Zilog Z-80 could run any program written for the 8080 and included twice as many built-in machine instructions.

Steve Wozniak completes the Apple-1

Designed by Sunnyvale, California native Steve Wozniak, and marketed by his friend Steve Jobs, the Apple-1 is a single-board computer for hobbyists. With an order for 50 assembled systems from Mountain View, California computer store The Byte Shop in hand, the pair started a new company, naming it Apple Computer, Inc. In all, about 200 of the boards were sold before Apple announced the follow-on Apple II a year later as a ready-to-use computer for consumers, a model which sold in the millions for nearly two decades.

Apple II introduced

Sold complete with a main logic board, switching power supply, keyboard, case, manual, game paddles, and cassette tape containing the game Breakout , the Apple-II finds popularity far beyond the hobbyist community which made up Apple’s user community until then. When connected to a color television set, the Apple II produced brilliant color graphics for the time. Millions of Apple IIs were sold between 1977 and 1993, making it one of the longest-lived lines of personal computers. Apple gave away thousands of Apple IIs to school, giving a new generation their first access to personal computers.

Tandy Radio Shack introduces its TRS-80

Performing far better than the company projections of 3,000 units for the first year, in the first month after its release Tandy Radio Shack´s first desktop computer — the TRS-80 — sells 10,000 units. The TRS-80 was priced at $599.95, included a Z80 microprocessor, video display, 4 KB of memory, a built-in BASIC programming language interpreter, cassette storage, and easy-to-understand manuals that assumed no prior knowledge on the part of the user. The TRS-80 proved popular with schools, as well as for home use. The TRS-80 line of computers later included color, portable, and handheld versions before being discontinued in the early 1990s.

The Commodore PET (Personal Electronic Transactor) introduced

Commodore PET

The first of several personal computers released in 1977, the PET comes fully assembled with either 4 or 8 KB of memory, a built-in cassette tape drive, and a 'chiclet' keyboard. The PET was popular with schools and for use as a home computer. It used a MOS Technologies 6502 microprocessor running at 1 MHz. After the success of the PET, Commodore remained a major player in the personal computer market into the 1990s.

The DEC VAX introduced

DEC VAX 11/780

Beginning with the VAX-11/780, the Digital Equipment Corporation (DEC) VAX family of computers rivals much more expensive mainframe computers in performance and features the ability to address over 4 GB of virtual memory, hundreds of times the capacity of most minicomputers. Called a “complex instruction set computer,” VAX systems were backward compatible and so preserved the investment owners of previous DEC computers had in software. The success of the VAX family of computers transformed DEC into the second-largest computer company in the world, as VAX systems became the de facto standard computing system for industry, the sciences, engineering, and research.

Atari introduces its Model 400 and 800 computers

Early Atari 400/800 advertisement

Shortly after delivery of the Atari VCS game console, Atari designs two microcomputers with game capabilities: the Model 400 and Model 800. The 400 served primarily as a game console, while the 800 was more of a home computer. Both faced strong competition from the Apple II, Commodore PET, and TRS-80 computers. Atari's 8-bit computers were influential in the arts, especially in the emerging DemoScene culture of the 1980s and '90s.

Motorola introduces the 68000 microprocessor

Die shot of Motorola 68000

Image by Pauli Rautakorpi

The Motorola 68000 microprocessor exhibited a processing speed far greater than its contemporaries. This high performance processor found its place in powerful work stations intended for graphics-intensive programs common in engineering.

Texas Instruments TI 99/4 is released

Texas Instruments TI 99/4 microcomputer

Based around the Texas Instruments TMS 9900 microprocessor running at 3 MHz, the TI 99/4 has one of the fastest CPUs available in a home computer. The TI99/4 had a wide variety of expansion boards, with an especially popular speech synthesis system that could also be used with TI's Speak & Spell educational game. The TI 99/4 sold well and led to a series of TI follow-on machines.

Commodore introduces the VIC-20

Commodore VIC-20

Commodore releases the VIC-20 home computer as the successor to the Commodore PET personal computer. Intended to be a less expensive alternative to the PET, the VIC-20 was highly successful, becoming the first computer to sell more than a million units. Commodore even used Star Trek television star William Shatner in advertisements.

The Sinclair ZX80 introduced

Sinclair ZX80

This very small home computer is available in the UK as a kit for £79 or pre-assembled for £99. Inside was a Z80 microprocessor and a built-in BASIC language interpreter. Output was displayed on the user’s home TV screen through use of an adapter. About 50,000 were sold in Britain, primarily to hobbyists, and initially there was a long waiting list for the system.

The Computer Programme debuts on the BBC

Title card- BBC’s The Computer Programme

The British Broadcasting Corporation’s Computer Literacy Project hoped “to introduce interested adults to the world of computers.” Acorn produces a popular computer, the BBC Microcomputer System, so viewers at home could follow along on their own home computers as they watched the program. The machine was expandable, with ports for cassette storage, serial interface and rudimentary networking. A large amount of software was created for the “BBC Micro,” including educational, productivity, and game programs.

Apollo Computer unveils its first workstation, its DN100

Apollo DN100

The DN100 is based on the Motorola 68000 microprocessor, high-resolution display and built-in networking - the three basic features of all workstations. Apollo and its main competitor, Sun Microsystems, optimized their machines to run the computer-intensive graphics programs common in engineering and scientific applications. Apollo was a leading innovator in the workstation field for more than a decade, and was acquired by Hewlett-Packard in 1989.

IBM introduces its Personal Computer (PC)

IBM's brand recognition, along with a massive marketing campaign, ignites the fast growth of the personal computer market with the announcement of its own personal computer (PC). The first IBM PC, formally known as the IBM Model 5150, was based on a 4.77 MHz Intel 8088 microprocessor and used Microsoft´s MS-DOS operating system. The IBM PC revolutionized business computing by becoming the first PC to gain widespread adoption by industry. The IBM PC was widely copied (“cloned”) and led to the creation of a vast “ecosystem” of software, peripherals, and other commodities for use with the platform.

Osborne 1 introduced

Weighing 24 pounds and costing $1,795, the Osborne 1 is the first mass-produced portable computer. Its price was especially attractive as the computer included very useful productivity software worth about $1,500 alone. It featured a 5-inch display, 64 KB of memory, a modem, and two 5.25-inch floppy disk drives.

Commodore introduces the Commodore 64

Commodore 64 system

The C64, as it is better known, sells for $595, comes with 64 KB of RAM and features impressive graphics. Thousands of software titles were released over the lifespan of the C64 and by the time it was discontinued in 1993, it had sold more than 22 million units. It is recognized by the 2006 Guinness Book of World Records as the greatest selling single computer of all time.

Franklin releases Apple II “clones”

Franklin Ace 100 microcomputer

Created almost five years after the original Apple II, Franklin's Ace 1000 main logic board is nearly identical to that in the Apple II+ computer, and other models were later cloned as well. Franklin was able to undercut Apple's pricing even while offering some features not available on the original. Initially, Franklin won a court victory allowing them to continue cloning the machines, but in 1988, Apple won a copyright lawsuit against Franklin, forcing them to stop making Apple II “clones.”

Sun Microsystems is founded

Sun-1 workstation

When Xerox PARC loaned the Stanford Engineering Department an entire Alto Ethernet network with laser printer, graduate student Andy Bechtolsheim re-designed it into a prototype that he then attached to Stanford’s computer network. Sun Microsystems grows out of this prototype. The roots of the company’s name came from the acronym for Stanford University Network (SUN). The company was incorporated by three 26-year-old Stanford alumni: Bechtolsheim, Vinod Khosla and Scott McNealy. The trio soon attracted UC Berkeley UNIX guru Bill Joy, who led software development. Sun helped cement the model of a workstation having an Ethernet interface as well as high-resolution graphics and the UNIX operating system.

Apple introduces the Lisa computer

Lisa is the first commercial personal computer with a graphical user interface (GUI). It was thus an important milestone in computing as soon Microsoft Windows and the Apple Macintosh would soon adopt the GUI as their user interface, making it the new paradigm for personal computing. The Lisa ran on a Motorola 68000 microprocessor and came equipped with 1 MB of RAM, a 12-inch black-and-white monitor, dual 5.25-inch floppy disk drives and a 5 MB “Profile” hard drive. Lisa itself, and especially its GUI, were inspired by earlier work at the Xerox Palo Alto Research Center.

Compaq Computer Corporation introduces the Compaq Portable

Compaq Portable

Advertised as the first 100% IBM PC-compatible computer, the Compaq Portable can run the same software as the IBM PC. With the success of the clone, Compaq recorded first-year sales of $111 million, the most ever by an American business in a single year. The success of the Portable inspired many other early IBM-compatible computers. Compaq licensed the MS-DOS operating system from Microsoft and legally reverse-engineered IBM’s BIOS software. Compaq's success launched a market for IBM-compatible computers that by 1996 had achieved an 83-percent share of the personal computer market.

Apple Computer launches the Macintosh

Apple Macintosh

Apple introduces the Macintosh with a television commercial during the 1984 Super Bowl, which plays on the theme of totalitarianism in George Orwell´s book 1984 . The ad featured the destruction of “Big Brother” – a veiled reference to IBM -- through the power of personal computing found in a Macintosh. The Macintosh was the first successful mouse-driven computer with a graphical user interface and was based on the Motorola 68000 microprocessor. Its price was $2,500. Applications that came as part of the package included MacPaint, which made use of the mouse, and MacWrite, which demonstrated WYSIWYG (What You See Is What You Get) word processing.

IBM releases its PC Jr. and PC/AT

The PC Jr. is marketed as a home computer but is too expensive and limited in performance to compete with many of the other machines in that market. It’s “chiclet” keyboard was also criticized for poor ergonomics. While the PC Jr. sold poorly, the PC/AT sold in the millions. It offered increased performance and storage capacity over the original IBM PC and sold for about $4,000. It also included more memory and accommodated high-density 1.2-megabyte 5 1/4-inch floppy disks.

PC's Limited is founded

PC’s Limited founder Michael Dell

In 1984, Michael Dell creates PC's Limited while still a student of the University of Texas at Austin. The dorm-room headquartered company sold IBM PC-compatible computers built from stock components. Dell dropped out of school to focus on his business and in 1985, the company produced the first computer of its own design, the Turbo PC, which sold for $795. By the early 1990s, Dell became one of the leading computer retailers.

The Amiga 1000 is released

Music composition on the Amiga 1000

Commodore’s Amiga 1000 is announced with a major event at New York's Lincoln Center featuring celebrities like Andy Warhol and Debbie Harry of the musical group Blondie. The Amiga sold for $1,295 (without monitor) and had audio and video capabilities beyond those found in most other personal computers. It developed a very loyal following while add-on components allowed it to be upgraded easily. The inside of the Amiga case is engraved with the signatures of the Amiga designers, including Jay Miner as well as the paw print of his dog Mitchy.

Compaq introduces the Deskpro 386 system

Promotional shot of the Compaq Deskpro 386s,

Compaq beats IBM to the market when it announces the Deskpro 386, the first computer on the market to use Intel´s new 80386 chip, a 32-bit microprocessor with 275,000 transistors on each chip. At 4 million operations per second and 4 kilobytes of memory, the 80386 gave PCs as much speed and power as older mainframes and minicomputers.

The 386 chip brought with it the introduction of a 32-bit architecture, a significant improvement over the 16-bit architecture of previous microprocessors. It had two operating modes, one that mirrored the segmented memory of older x86 chips, allowing full backward compatibility, and one that took full advantage of its more advanced technology. The new chip made graphical operating environments for IBM PC and PC-compatible computers practical. The architecture that allowed Windows and IBM OS/2 has remained in subsequent chips.

IBM releases the first commercial RISC-based workstation

Reduced instruction set computers (RISC) grow out of the observation that the simplest 20 percent of a computer´s instruction set does 80 percent of the work. The IBM PC-RT had 1 MB of RAM, a 1.2-megabyte floppy disk drive, and a 40 MB hard drive. It performed 2 million instructions per second, but other RISC-based computers worked significantly faster.

The Connection Machine is unveiled

Connection Machine CM-1

Daniel Hillis of Thinking Machines Corporation moves artificial intelligence a step forward when he develops the controversial concept of massive parallelism in the Connection Machine CM-1. The machine used up to 65,536 one-bit processors and could complete several billion operations per second. Each processor had its own small memory linked with others through a flexible network that users altered by reprogramming rather than rewiring. The machine´s system of connections and switches let processors broadcast information and requests for help to other processors in a simulation of brain-like associative recall. Using this system, the machine could work faster than any other at the time on a problem that could be parceled out among the many processors.

Acorn Archimedes is released

Acorn Archimedes microcomputer

Acorn's ARM RISC microprocessor is first used in the company's Archimedes computer system. One of Britain's leading computer companies, Acorn continued the Archimedes line, which grew to nearly twenty different models, into the 1990s. Acorn spun off ARM as its own company to license microprocessor designs, which in turn has transformed mobile computing with ARM’s low power, high-performance processors and systems-on-chip (SoC).

IBM introduces its Personal System/2 (PS/2) machines

The first IBM system to include Intel´s 80386 chip, the company ships more than 1 million units by the end of the first year. IBM released a new operating system, OS/2, at the same time, allowing the use of a mouse with IBM PCs for the first time. Many credit the PS/2 for making the 3.5-inch floppy disk drive and video graphics array (VGA) standard for IBM computers. The system was IBM's response to losing control of the PC market with the rise of widespread copying of the original IBM PC design by “clone” makers.

Apple co-founder Steve Jobs unveils the NeXT Cube

Steve Jobs, forced out of Apple in 1985, founds a new company – NeXT. The computer he created, an all-black cube was an important innovation. The NeXT had three Motorola microprocessors and 8 MB of RAM. Its base price was $6,500. Some of its other innovations were the inclusion of a magneto-optical (MO) disk drive, a digital signal processor and the NeXTSTEP programming environment (later released as OPENSTEP). This object-oriented multitasking operating system was groundbreaking in its ability to foster rapid development of software applications. OPENSTEP was used as one of the foundations for the new Mac OS operating system soon after NeXT was acquired by Apple in 1996.

Laser 128 is released

Laser 128 Apple II clone

VTech, founded in Hong Kong, had been a manufacturer of Pong-like games and educational toys when they introduce the Laser 128 computer. Instead of simply copying the basic input output system (BIOS) of the Apple II as Franklin Computer had done, they reversed engineered the system and sold it for US $479, a much lower price than the comparable Apple II. While Apple sued to remove the Laser 128 from the market, they were unsuccessful and the Laser remained one of the very few Apple “clones” for sale.

Intel introduces the 80486 microprocessor

Intel 80486 promotional photo

Intel released the 80486 microprocessor and the i860 RISC/coprocessor chip, each of which contained more than 1 million transistors. The RISC microprocessor had a 32-bit integer arithmetic and logic unit (the part of the CPU that performs operations such as addition and subtraction), a 64-bit floating-point unit, and a clock rate of 33 MHz.

The 486 chips remained similar in structure to their predecessors, the 386 chips. What set the 486 apart was its optimized instruction set, with an on-chip unified instruction and data cache and an optional on-chip floating-point unit. Combined with an enhanced bus interface unit, the microprocessor doubled the performance of the 386 without increasing the clock rate.

Macintosh Portable is introduced

Macintosh Portable

Apple had initially included a handle in their Macintosh computers to encourage users to take their Macs on the go, though not until five years after the initial introduction does Apple introduce a true portable computer. The Macintosh Portable was heavy, weighing sixteen pounds, and expensive (US$6,500). Sales were weaker than projected, despite being widely praised by the press for its active matrix display, removable trackball, and high performance. The line was discontinued less than two years later.

Intel's Touchstone Delta supercomputer system comes online

Intel Touchstone Delta supercomputer

Reaching 32 gigaflops (32 billion floating point operations per second), Intel’s Touchstone Delta has 512 processors operating independently, arranged in a two-dimensional communications “mesh.” Caltech researchers used this supercomputer prototype for projects such as real-time processing of satellite images, and for simulating molecular models in AIDS research. It would serve as the model for several other significant multi-processor systems that would be among the fastest in the world.

Babbage's Difference Engine #2 is completed

The Difference Engine #2 at the Science Museum, London

Based on Charles Babbage's second design for a mechanical calculating engine, a team at the Science Museum in London sets out to prove that the design would have worked as planned. Led by curator Doron Swade the team built Babbage’s machine in six years, using techniques that would have been available to Babbage at the time, proving that Babbage’s design was accurate and that it could have been built in his day.

PowerBook series of laptops is introduced

PowerBook 100 laptop computer

Apple's Macintosh Portable meets with little success in the marketplace and leads to a complete redesign of Apple's line of portable computers. All three PowerBooks introduced featured a built-in trackball, internal floppy drive, and palm rests, which would eventually become typical of 1990s laptop design. The PowerBook 100 was the entry-level machine, while the PowerBook 140 was more powerful and had a larger memory. The PowerBook 170 was the high-end model, featuring an active matrix display, faster processor, as well as a floating point unit. The PowerBook line of computers was discontinued in 2006.

DEC announces Alpha chip architecture

DEC Alpha chip die-shot

Designed to replace the 32-bit VAX architecture, the Alpha is a 64-bit reduced instruction set computer (RISC) microprocessor. It was widely used in DEC's workstations and servers, as well as several supercomputers like the Chinese Sunway Blue Light system, and the Swiss Gigabooster. The Alpha processor designs were eventually acquired by Compaq, which, along with Intel, phased out the Alpha architecture in favor of the HP/Itanium microprocessor.

Intel Paragon is operational

Intel Paragon system

Based on the Touchstone Delta computer Intel had built at Caltech, the Paragon is a parallel supercomputer that uses 2,048 (later increased to more than four thousand) Intel i860 processors. More than one hundred Paragons were installed over the lifetime of the system, each costing as much as five million dollars. The Paragon at Caltech was named the fastest supercomputer in the world in 1992. Paragon systems were used in many scientific areas, including atmospheric and oceanic flow studies, and energy research.

Apple ships the first Newton

The Apple Newton Personal Digital Assistant

Apple enters the handheld computer market with the Newton. Dubbed a “Personal Digital Assistant” by Apple President John Sculley in 1992, the Newton featured many of the features that would define handheld computers in the following decades. The handwriting recognition software was much maligned for inaccuracy. The Newton line never performed as well as hoped and was discontinued in 1998.

Intel's Pentium microprocessor is released

HP Netserver LM, one of the first to use Intel's Pentium

The Pentium is the fifth generation of the ‘x86’ line of microprocessors from Intel, the basis for the IBM PC and its clones. The Pentium introduced several advances that made programs run faster such as the ability to execute several instructions at the same time and support for graphics and music.

RISC PC is released

Acorn RISC PC

Replacing their Archimedes computer, the RISC PC from UK's Acorn Computers uses the ARMv3 RISC microprocessor. Though it used a proprietary operating system, RISC OS, the RISC PC could run PC-compatible software using the Acorn PC Card. The RISC PC was used widely in UK broadcast television and in music production.

BeBox is released

BeBox computer

Be, founded by former Apple executive Jean Louis Gassée and a number of former Apple, NeXT and SUN employees, releases their only product – the BeBox. Using dual PowerPC 603 CPUs, and featuring a large variety of peripheral ports, the first devices were used for software development. While it did not sell well, the operating system, Be OS, retained a loyal following even after Be stopped producing hardware in 1997 after less than 2,000 machines were produced.

IBM releases the ThinkPad 701C

IBM ThinkPad 701C

Officially known as the Track Write, the automatically expanding full-sized keyboard used by the ThinkPad 701 is designed by inventor John Karidis. The keyboard was comprised of three roughly triangular interlocking pieces, which formed a full-sized keyboard when the laptop was opened -- resulting in a keyboard significantly wider than the case. This keyboard design was dubbed “the Butterfly.” The need for such a design was lessened as laptop screens grew wider.

Palm Pilot is introduced

Ed Colligan, Donna Dubinsky, and Jeff Hawkins

Palm Inc., founded by Ed Colligan, Donna Dubinsky, and Jeff Hawkins, originally created software for the Casio Zoomer personal data assistant. The first generation of Palm-produced devices, the Palm 1000 and 5000, are based around a Motorola microprocessor running at 16MHz, and uses a special gestural input language called “Graffiti,” which is quick to learn and fast. Palm could be connected to a PC or Mac using a serial port to synchronize – “sync” – both computer and Palm. The company called it a ‘connected organizer’ rather than a PDA to emphasize this ability.

Sony Vaio series is begun

Sony Vaio laptop

Sony had manufactured and sold computers in Japan, but the VAIO signals their entry into the global computer market. The first VAIO, a desktop computer, featured an additional 3D interface on top of the Windows 95 operating system as a way of attracting new users. The VAIO line of computers would be best known for laptops were designed with communications and audio-video capabilities at the forefront, including innovative designs that incorporated TV and radio tuners, web cameras, and handwriting recognition. The line was discontinued in 2014.

ASCI Red is operational

ASCI Red supercomputers

The Advanced Strategic Computing Initiative (ASCI) needed a supercomputer to help with the maintenance of the US nuclear arsenal following the ban on underground nuclear testing. The ASCI Red, based on the design of the Intel Paragon, was built by IBM and delivered to Sandia National Laboratories. Until the year 2000, it was the world's fastest supercomputer, able to achieve peak performance of 1.3 teraflops, (about 1.3 trillion calculations per second).

Linux-based Supercomputing

Linux Supercomputer

The first supercomputer using the Linux operating system, consumer, off-the shelf parts, and a high-speed, low-latency interconnection network, was developed by David A. Bader while at the University of New Mexico. From this successful prototype design, Bader led the development of “RoadRunner”, the first Linux supercomputer for open use by the national science and engineering community via the National Science Foundation's National Technology Grid. RoadRunner was put into production use in April 1999. Within a decade this design became the predominant architecture for all major supercomputers in the world.

The iMac, a range of all-in-one Macintosh desktop computers, is launched

iMac poster

Apple makes a splash with its Bondi Blue iMac, which sells for about $1,300. Customers got a machine with a 233-MHz G3 processor, 4GB hard drive, 32MB of RAM, a CD-ROM drive, and a 15" monitor. The machine was noted for its ease-of-use and included a 'manual' that contained only a few pictures and less than 20 words. As Apple’s first new product under the leadership of a returning Steve Jobs, many consider this the most significant step in Apple's return from near-bankruptcy in the middle 1990s.

First camera phone introduced

Sony-built J-Phone J-SH04

Japan's SoftBank introduces the first camera phone, the J-Phone J-SH04; a Sharp-manufactured digital phone with integrated camera. The camera had a maximum resolution of 0.11 megapixels a 256-color display, and photos could be shared wirelessly. The J-Phone line would quickly expand, releasing a flip-phone version just a month later. Cameras would become a significant part of most phones within a year, and several countries have even passed laws regulating their use.

Earth Simulator is world's fastest supercomputer

Earth Simulator Supercomputer

Developed by the Japanese government to create global climate models, the Earth Simulator is a massively parallel, vector-based system that costs nearly 60 billion yen (roughly $600 million at the time). A consortium of aerospace, energy, and marine science agencies undertook the project, and the system was built by NEC around their SX-6 architecture. To protect it from earthquakes, the building housing it was built using a seismic isolation system that used rubber supports. The Earth Simulator was listed as the fastest supercomputer in the world from 2002 to 2004.

Handspring Treo is released

Colligan, Dubinsky, Hawkins (left to right)

Leaving Palm Inc., Ed Colligan, Donna Dubinsky, and Jeff Hawkins found Handspring. After retiring their initial Visor series of PDAs, Handspring introduced the Treo line of smartphones, designed with built-in keyboards, cameras, and the Palm operating system. The Treo sold well, and the line continued until Handspring was purchased by Palm in 2003.

PowerMac G5 is released

PowerMac G5 tower computer

With a distinctive anodized aluminum case, and hailed as the first true 64-bit personal computer, the Apple G5 is the most powerful Macintosh ever released to that point. While larger than the previous G4 towers, the G5 had comparatively limited space for expansion. Virginia Tech used more than a thousand PowerMac G5s to create the System X cluster supercomputer, rated #3 in November of that year on the world’s TOP500 fastest computers.

Arduino starter kit

Harkening back to the hobbyist era of personal computing in the 1970s, Arduino begins as a project of the Interaction Design Institute, Ivrea, Italy. Each credit card-sized Arduino board consisted of an inexpensive microcontroller and signal connectors which made Arduinos ideal for use in any application connecting to or monitoring the outside world. The Arduino used a Java-based integrated development environment and users could access a library of programs, called “Wiring,” that allowed for simplified programming. Arduino soon became the main computer platform of the worldwide “Maker” movement.

Lenovo acquires IBM's PC business

IBM and Lenovo logos

Nearly a quarter century after IBM launched their PC in 1981, they had become merely another player in a crowded marketplace. Lenovo, China's largest manufacturer of PCs, purchased IBM's personal computer business in 2005, largely to gain access to IBM's ThinkPad line of computers and sales force. Lenovo became the largest manufacturer of PCs in the world with the acquisition, later also acquiring IBM's server line of computers.

NASA Ames Research Center supercomputer Columbia

Columbia Supercomputer system made up of SGI Altix

Named in honor of the space shuttle which broke-up on re-entry, the Columbia supercomputer is an important part of NASA's return to manned spaceflight after the 2003 disaster. Columbia was used in space vehicle analysis, including studying the Columbia disaster, but also in astrophysics, weather and ocean modeling. At its introduction, it was listed as the second fastest supercomputer in the world and this single system increased NASA's supercomputing capacity 10-fold. The system was kept at NASA Ames Research Center until 2013, when it was removed to make way for two new supercomputers.

One Laptop Per Child initiative begins

OLPC XO laptop computer

At the 2006 World Economic Forum in Davos, Switzerland, the United Nations Development Program (UNDP) announces it will create a program to deliver technology and resources to targeted schools in the least developed countries. The project became the One Laptop per Child Consortium (OLPC) founded by Nicholas Negroponte, the founder of MIT's Media Lab. The first offering to the public required the buyer to purchase one to be given to a child in the developing world as a condition of acquiring a machine for themselves. By 2011, over 2.4 million laptops had been shipped.

The Amazon Kindle is released

Amazon Kindle

Many companies have attempted to release electronic reading systems dating back to the early 1990s. Online retailer Amazon released the Kindle, one of the first to gain a large following among consumers. The first Kindle featured wireless access to content via Amazon.com, along with an SD card slot allowing increased storage. The first release proved so popular there was a long delay in delivering systems on release. Follow-on versions of the Kindle added further audio-video capabilities.

The Apple iPhone is released

Apple iPhone

Apple launches the iPhone - a combination of web browser, music player and cell phone - which could download new functionality in the form of "apps" (applications) from the online Apple store. The touchscreen enabled smartphone also had built-in GPS navigation, high-definition camera, texting, calendar, voice dictation, and weather reports.

The MacBook Air is released

Steve Jobs introducing MacBook Air

Apple introduces their first ultra notebook – a light, thin laptop with high-capacity battery. The Air incorporated many of the technologies that had been associated with Apple's MacBook line of laptops, including integrated camera, and Wi-Fi capabilities. To reduce its size, the traditional hard drive was replaced with a solid-state disk, the first mass-market computer to do so.

IBM's Roadrunner supercomputer is completed

Computer-enhanced image of IBM’s Roadrunner

The Roadrunner is the first computer to reach a sustained performance of 1 petaflop (one thousand trillion floating point operations per second). It used two different microprocessors: an IBM POWER XCell L8i and AMD Opteron. It was used to model the decay of the US nuclear arsenal, analyze financial data, and render 3D medical images in real-time. An offshoot of the POWER XCell8i chip was used as the main processor in the Sony PlayStation 3 game console.

Jaguar Supercomputer at Oak Ridge upgraded

Originally a Cray XT3 system, the Jaguar is a massively parallel supercomputer at Oak Ridge National Laboratory, a US science and energy research facility. The system cost more than $100 million to create and ran a variation of the Linux operating system with up to 10 petabytes of storage. The Jaguar was used to study climate science, seismology, and astrophysics applications. It was the fastest computer in the world from November 2009 to June 2010.

Apple Retina Display

Introduction of the iPhone 4 with retina display

Since the release of the Macintosh in 1984, Apple has placed emphasis on high-resolution graphics and display technologies. In 2012, Apple introduced the Retina display for the MacBook Pro laptop and iPad tablet. With a screen resolution of up to 400 pixels-per-inch (PPI), Retina displays approached the limit of pixel visibility to the human eye. The display also used In Plane Switching (IPS) technology, which allowed for a wider viewing angle and improved color accuracy. The Retina display became standard on most of the iPad, iPhone, MacBook, and Apple Watch product lines.

China's Tianhe supercomputers are operational

Tianhe-1A Supercomputer

With a peak speed of over a petaflop (one thousand trillion calculations per second), the Tianhe 1 (translation: Milky Way 1) is developed by the Chinese National University of Defense Technology using Intel Xeon processors combined with AMD graphic processing units (GPUs). The upgraded and faster Tianhe-1A used Intel Xeon CPUs as well, but switched to nVidia's Tesla GPUs and added more than 2,000 Fei-Tang (SPARC-based) processors. The machines were used by the Chinese Academy of Sciences to run massive solar energy simulations, as well as some of the most complex molecular studies ever undertaken.

The Apple iPad is released

Steve Jobs introducing the iPad

The iPad combines many of the popular capabilities of the iPhone, such as built-in high-definition camera, access to the iTunes Store, and audio-video capabilities, but with a nine-inch screen and without the phone. Apps, games, and accessories helped spur the popularity of the iPad and led to its adoption in thousands of different applications from movie making, creating art, making music, inventory control and point-of-sale systems, to name but a few.

IBM Sequoia is delivered to Lawrence Livermore Labs

Built by IBM using their Blue Gene/Q supercomputer architecture, the Sequoia system is the world's fastest supercomputer in 2012. Despite using 98,304 PowerPC chips, Sequoia's relatively low power usage made it unusually efficient. Scientific and defense applications included studies of human electrophysiology, nuclear weapon simulation, human genome mapping, and global climate change.

Nest Learning Thermostat is Introduced

Nest Learning Thermostat

The Nest Learning Thermostat is an early product made for the emerging “Internet of Things,” which envisages a world in which common everyday devices have network connectivity and can exchange information or be controlled. The Nest allowed for remote access to a user’s home’s thermostat by using a smartphone or tablet and could also send monthly power consumption reports to help save on energy bills. The Nest would remember what temperature users preferred by ‘training’ itself to monitor daily use patterns for a few days then adopting that pattern as its new way of controlling home temperature.

Raspberry Pi, a credit-card-size single board computer, is released as a tool to promote science education

Raspberry Pi computer

Conceived in the UK by the Raspberry Pi Foundation, this credit card-sized computer features ease of use and simplicity making it highly popular with students and hobbyists. In October 2013, the one millionth Raspberry Pi was shipped. Only one month later, another one million Raspberry Pis were delivered. The Pi weighed only 45 grams and initially sold for only $25-$35 U.S. Dollars.

University of Michigan Micro Mote is Completed

The University of Michigan Micro Mote is the smallest computer in the world. The motes, measuring just over 1 cubic millimeter, were powered by a tiny battery and could collect sunlight through a photocell, enough to supply the tiny amount of energy a mote consumes -- about one trillionth of a watt. Three types of mote were initially introduced: two that measure temperature or pressure, and one that could take images. Since then, motes that recognize different sounds, measure light, track position, and record brain activity have been developed.

Motes are also known as "smart dust," since their tiny size and low cost make them inexpensive enough to "sprinkle" in the real world as sensors. An ecologist, for example, could sprinkle thousands of motes from the air onto a field and measure soil and air temperature, moisture, and sunlight, yielding accurate real-time data about the environment.

Apple Watch

Apple Store’s display of newly introduced Apple Watches

Building a computer into the watch form factor has been attempted many times but the release of the Apple Watch leads to a new level of excitement. Incorporating a version of Apple's iOS operating system, as well as sensors for environmental and health monitoring, the Apple Watch was designed to be incorporated into the Apple environment with compatibility with iPhones and Mac Books. Almost a million units were ordered on the day of release. The Watch was received with great enthusiasm, but critics took issue with the somewhat limited battery life and high price.

Exhibit Design and Development Team

Exhibit content team.