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CA644, System Software
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History, Part 1

CA644, System Software

Dr. Niall McMahon


If you print these slides, think about using two pages per sheet although don't worry too much about it!


Dr. Niall McMahon

Drawing on previous work by:
Dr. Graham Healy and others.
And sources credited in the references.
Autumn 2022.


This very short review of "the history of computing" is a work in progress. It's not intended to be a definitive guide. I will improve it if I find the time and I will place a "canonical" version of these notes in a more permanent location on my website. Many people have done a lot of hard work building complete histories and technical overviews; as I discover these I will link to them.

There are many super books on this topic. Andrew S. Tanenbaum lists a few - which I haven't read - in his book, Structured Computer Organization, in Section 1.2, Milestones in Computer Architecture. In this section, Tanenbaum divides the history of computer architecture in to five generations.

See my history of computing links page for a list of online references.

Circa 2700 BCE

  • Abacus. Still in use today in Asia.


The invention of the true mechanical calculator.

  • First known mechanical calculator built by Blaise Pascal in 1642.
  • A 1617 invention by John Napier, in Scotland, was a calculation aid based on logarithmic tables but not a true calculating machine.
  • Napier's ideas were developed by Edmund Gunter and consolidated into the slide rule in the 1630s.


Mechanical automation. In France with the famous Jacquard looms.


  • Weaving delicate patterns requires certain threads to be lifted while the shuttle passes underneath.
  • It's a tricky task and must be done right at the right time; very tiring for a weaver.
  • Joseph Marie Jacquard semi-automated this process by using punch cards.
  • Each card is examined in turn - according to a tempo - by pressing rods against the cards.
  • Different patterns of holes configure the threads differently.
  • The machine debuted in 1801 and by 1812, 10,000 Jacquard looms were in use in France.
  • There are similarities between weaving and calculating. Both follow algorithms, i.e. explicit, precise, unambiguous, mechanically-executable sequence of elementary instructions, usually intended to accomplish a specific purpose. This definition is from the introduction of Jeff Erickson's book.


The application of automation to calculation.

Charles Babbage and Ada Lovelace

  • Jacquard's programmable looms inspired Charles Babbage, a professor of mathematics at the University of Cambridge.
  • He designed programmable mechanical calulating machines.
  • The most famous built was the Difference Engine and the more complex Analytical Engine.
  • Ada Lovelace proposed a program to calculate the Bernoulli numbers using Babbage's machine, making her the first programmer of a computing machine.


  • The Tabulating Machine Company, the precursor to IBM, was founded in 1890 to build a machine that could tabulate data from US census.
  • The machine used electrical current to sense holes in punch cards.


  • Alan Turing, who worked on code-cracking for the UK during the war, designed an abstract computing machine which is now called a Turing machine.
  • This is a useful theortical idealisation of a computer.
  • The Universal Turing Machine, is a further abstraction that can describe any kind of computer.
  • John von Neumann was also working on ideas in computing at this time.
  • The word calculator meant a person that does calculation at this time, often using slide rules. Slide rules were widely used until eclipsed by electronic calculators in the 1970s.


1945 - ENIAC and von Neumann

Electronic computers based on vacuum tubes and stored programs.

  • ENIAC, Electronic Numerical Integrator and Computer, was built in late wartime in the US to calculate trajectories. Designed by Eckert and Mauchley.
  • Kathleen McNulty (also Antonelli), was an Irish-American programmer of the 25 metre long ENIAC - one of computing buildings in DCU is named for her.
  • The von Neumann architecture was described by John von Neumann in a draft report he co-authored called, First Draft of a Report on the EDVAC. You can find a copy of the report thanks to MIT here, First Draft of a Report on the EDVAC.

1948 - Transistors

  • The transistor was invented in Bell Labs by Bardeen, Brattain and Shockley.


The widespread deployment of transistors begins in 1955.

  • Integrated circuits invented in 1958 allowing dozens of transistors on a silicon chip; vastly increased data processing per unit volume.
  • Punch cards still used to program machines, although electrical rather than mechanical systems.
  • Keyboards becoming more common and nascent graphical user interfaces.


The widespread deployment of integrated circuits begins in 1965. Mainframe business computing, operating systems and multiprogramming, minicomputers and networks.

1961 - Apollo

1964 - IBM OS/360

  • OS/360 was the first multiprogramming operating system made commercially available by IBM.

1965 - DEC PDP-8

1968 - Intel

  • Founded by Gordon Moore and Robert Noyce.
  • Short for "Integrated Electronics".
  • Intel 4004, with 2,300 MOS (Metal Oxide Silicon) transistors.

1969 - ArpaNet


Microcomputers and home computing.

1972 - Atari

  • Founded by Nolan Bushnell and Ted Dabney in Sunnyvale, California.
  • Pioneered popular arcade games and, in 1977, the Atari 2600 revolutionised consoles.
  • Although Atari was not the first arcade games manufacturer or the first to imagine home consoles, it did successfully market simple, playable games.

1973 - Unix

Unix was developed by Dennis Ritchie and Ken Thompson at Bell Labs in the 60s/70s. According to Ritchie, it was designed to be a general-purpose, multi-user, interactive operating system for the Digital Equipment Corporation PDP-II/40 and 11/45 computers.

1975 - MITS Altair 8800

  • MITS, in Albuquerque in New Mexico, built the Altair 8800 microcomputer in 1975.
  • It was the leading kit computer, i.e. you had to assemble it yourself.
  • The Altair 8800 and MITS in part led to the formation of Microsoft.

1975 - Microsoft

  • Founded by Bill Gates and Paul Allen in Albuquerque, New Mexico, to build software for the Altair 8800.
  • In 1980 developed an operating system called Xenix.
  • MS-DOS, developed from a clone of another operating system built by Seattle Computer Products for the 8086 Intel chips.

1976 - Apple

1977 - BSD

  • Berkeley Software Distribution, based on Unix, developed at The University of California.
  • AT&T sucdessfully sued UC Berkeley for using Unix code owned by the company.

Other Things in the 1970s

  • 1971: The first floppy disk.
  • 1973: Xerox invents Ethernet, a family of technologies that underpin modern networks.


Consumer hardware; consumer software; portable computing.

1981 - IBM's first PC

  • The IBM PC quickly displaced the Apple II as the best selling home computer.
  • Powered by the Intel 8088 microprocessor, precursor to today's designs.
  • PCs were shipped with a version of MS-DOS, Microsoft's command-line operating system, branded as IBM PC DOS.

1983 - The GNU Project

  • The GNU Project - GNU is a recursive acronym for GNU's Not Unix! - Founded by Richard Stallman.
  • Aim to create a free Unix-like operating system.
  • Distributed using the GNU Public License (GPL).
  • An incomplete kernel called Hurd developed by early 1990s.

1984 - Apple Macintosh

  • The Macintosh was Apple's attempt to take on IBM and to keep the company relevant.
  • It featured Apple's graphical user interface (GUI) and updated operating system, MAC OS.
  • It didn't take off until 1987 after several upgrades.

1984 - Dell

  • Founded by Michael Dell in his college dorm at UT Texas in Austin.
  • Innovation was to build IBM-type machines with upgraded components.

1985 - Microsoft Windows 1.0

  • This was a GUI for MS-DOS.
  • It became very popular after Version 3.0 in 1990.

1980s - Many Other Honourable Mentions

  • 1981 - Sinclair ZX81. Designed and built in Britain, introduced many to home computing. Clive Sinclair died in 2021.
  • 1982 - Commodore 64 by Commodore Business Machines in Pennsylvania. This successful machine was built until 1993. It had an ecosystem of some 10,000 programs and was relatively affordable, about $1,500 in today's money.


The 1990s saw a maturing of the PC into modern multimedia systems with user-friendly operating systems. A computer at home became increasingly common in the West. The 1990s saw the birth of the World Wide Web and the first wave of internet tech companies.

Early 90s - CD ROM

  • Allowed easy distribution of large media-heavy programs.

1993 - The World Wide Web

1994 - Amazon

  • Jeff Bezos founds Amazon in 1994, making deliveries himself.

1994 - Linux

  • Built by Linus Torvalds and a team of volunteers.
  • Developed using the GNU Hurd kernel.
  • Free and open rival to Microsoft and Apple.
  • Powers most servers on the Internet in 2021.

1995 - Windows 95

1998 - Google

  • Founded by Larry Page and Sergey Brin in a garage close to Stanford.
  • Innovation was the idea to use back-links to determine page rank.
  • Before Google, Alta Vista was probably the most popular search engine.

1995 - 2001

The DotCom bubble and bust all happened in this period. There was an explosion in the number of online companies and ambitious service offerings but the technology was not quite there to make it all work. The resulting disappointments became a worry for investors leading to a bust and a short recession that began in 2000 but that did not become widespread, leading to lay-offs, until the following year.


This era is generally technology positive as more of the general population move online; laptops are popular. The second wave of new internet companies. "Web 2.0", a moniker that captures the era of platforms and interactive websites. Cloud computing grows from 2002.


  • Maturing Web 2.0 and a new wave of companies.
  • Mobile computing and phones everywhere.
  • Video and image dominate.
  • Misinformation, disinformation and spying.
  • Machine learning and artificial intelligence.
  • Consolidation of the Internet for most people around a handful of companies.
  • 2010: Ryanair makes online check-in mandatory as most of the flying population have some access to the Internet.
  • Instagram and many social apps including WhatsApp. (Instagram and WhatsApp are now owned by Meta.)
  • Video on demand services, e.g. Netflix.
  • Niche technical services built for cloud computing, e.g. Stripe.
  • Google Deepmind and many machine learning companies.


It's too early to write a history but characterised by further consolidation of the Internet around a handful of companies and a small (but growing?) technology and corporation backlash. Some of this is expressed through the explosion in interest in crypto-currencies and meme-stocks during the Pandemic.

Some fragmentation of social platforms with the decline of the original Facebook platform and the rise of WhatsApp and Telegram. Decentralised communications platforms, e.g. Discord, grow in popularity on campus and in technology circles.