The ILLIAC I (Illinois Automatic Computer), a pioneering

computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations ( computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These prog ...

in the ILLIAC series of computers built in 1952 by the

University of Illinois The University of Illinois Urbana-Champaign (U of I, Illinois, University of Illinois, or UIUC) is a public land-grant research university in Illinois in the twin cities of Champaign and Urbana. It is the flagship institution of the Uni ...

, was the first computer built and owned entirely by a United States educational institution.

Computer

The project was the brainchild of Ralph Meagher and

Abraham H. Taub Abraham Haskel Taub (; February 1, 1911 – August 9, 1999) was a distinguished American mathematician and physicist, well known for his important contributions to the early development of general relativity, as well as differential geometry and ...

, who both were associated with Princeton's Institute for Advanced Study before coming to the University of Illinois. The ILLIAC I became operational on September 1, 1952. It was the second of two identical computers, the first of which was ORDVAC, also built at the University of Illinois. These two machines were the first pair of machines to run the same instruction set. ILLIAC I was based on the IAS machine

Von Neumann architecture The von Neumann architecture — also known as the von Neumann model or Princeton architecture — is a computer architecture based on a 1945 description by John von Neumann, and by others, in the '' First Draft of a Report on the EDVAC''. T ...

as described by mathematician

John von Neumann John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest c ...

in his influential '' First Draft of a Report on the EDVAC''. Unlike most computers of its era, the ILLIAC I and ORDVAC computers were twin copies of the same design, with

software compatibility A family of computer models is said to be compatible if certain software that runs on one of the models can also be run on all other models of the family. The computer models may differ in performance, reliability or some other characteristic. T ...

. The computer had 2,800

vacuum tube A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as ...

s, measured 10 ft (3 m) by 2 ft (0.6 m) by 8½ ft (2.6 m) (L×B×H), and weighed . ILLIAC I was very powerful for its time; in 1956, it had more computing power than all of

Bell Telephone Laboratories Nokia Bell Labs, originally named Bell Telephone Laboratories (1925–1984), then AT&T Bell Laboratories (1984–1996) and Bell Labs Innovations (1996–2007), is an American industrial research and scientific development company owned by mult ...

. Because the lifetime of the tubes within ILLIAC was about a year, the machine was shut down every day for "preventive maintenance" when older vacuum tubes would be replaced in order to increase reliability. Visiting scholars from Japan assisted in the design of the ILLIAC series of computers, and later developed the

MUSASINO-1 The MUSASINO-1 was one of the earliest electronic digital computers built in Japan. Construction started at the Electrical Communication Laboratories of NTT at Musashino, Tokyo in 1952 and was completed in July 1957. The computer was used until Ju ...

computer in Japan. ILLIAC I was retired in 1962, when the ILLIAC II became operational.

Innovations

* 1955 –

Lejaren Hiller Lejaren Arthur Hiller Jr. (February 23, 1924, New York City – January 26, 1994, Buffalo, New York)Lejaren H ...

and Leonard Isaacson used ILLIAC I to compose the ''

Illiac Suite ''Illiac Suite'' (later retitled String Quartet No. 4)Andrew Stiller, "Hiller, Lejaren (Arthur)", ''Grove Music Online'' (reviewed December 3, 2010; accessed December 14, 2014). is a 1957 composition for string quartet which is generally agreed t ...

'' which was one of the first pieces of music to be written with the aid of a computer. * 1957 – Mathematician

Donald B. Gillies Donald Bruce Gillies (October 15, 1928 – July 17, 1975) was a Canadian computer scientist and mathematician who worked in the fields of computer design, game theory, and minicomputer programming environments. Early life and education ...

, physicist James E. Snyder, and astronomers George C. McVittie, S. P. Wyatt, Ivan R. King and George W. Swenson of the

used the ILLIAC I computer to calculate the orbit of the

Sputnik 1 Sputnik 1 (; see § Etymology) was the first artificial Earth satellite. It was launched into an elliptical low Earth orbit by the Soviet Union on 4 October 1957 as part of the Soviet space program. It sent a radio signal back to Earth for ...

satellite within two days of its launch. * 1960 – The first version of the

PLATO Plato ( ; grc-gre, Πλάτων ; 428/427 or 424/423 – 348/347 BC) was a Greek philosopher born in Athens during the Classical period in Ancient Greece. He founded the Platonist school of thought and the Academy, the first institution ...

computer-based education system was implemented on the ILLIAC I by a team led by

Donald Bitzer Donald L. Bitzer (born January 1, 1934) is an American electrical engineer and computer scientist. He was the co-inventor of the plasma display, is largely regarded as the "father of PLATO", and has made a career of improving classroom productivit ...

. It serviced a single user. In early 1961, version 2 of PLATO serviced two simultaneous users.

References

External links

ILLIAC I history including computer music

ILLIAC I documentation
at bitsavers.org * I. R. King, G. C. McVittie, G. W. Swenson, Jr., and S. P. Wyatt, Jr., "Further observations of the first satellite," ''

Nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are ...

'', No. 4593, November 9, 1957, p. 943. * Digital Computer, 'electronic brain' at the University of Illinois. Digital Public Library of Americ

Photos from University of Illinois archives
{{Mainframes IAS architecture computers Vacuum tube computers Computer-related introductions in 1952

Computer

Innovations

See also

References

External links