Titan was the prototype of the Atlas 2 computer developed by

Ferranti Ferranti International PLC or simply Ferranti was a UK-based electrical engineering and equipment firm that operated for over a century, from 1885 until its bankruptcy in 1993. At its peak, Ferranti was a significant player in power grid system ...

and the University of Cambridge Mathematical Laboratory in

Cambridge Cambridge ( ) is a List of cities in the United Kingdom, city and non-metropolitan district in the county of Cambridgeshire, England. It is the county town of Cambridgeshire and is located on the River Cam, north of London. As of the 2021 Unit ...

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

. It was designed starting in 1963, and in operation from 1964 to 1973.

History

In 1961, the

University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

found itself unable to fund a suitably powerful computer for its needs at the time, so the university purchased from Ferranti the main Atlas processing units and then jointly designed the memory and peripheral equipment. The joint effort led to a cheaper and simpler version of the Atlas that Ferranti could market, leaving Cambridge with the prototype version, named Titan. The Atlas hardware arrived in Cambridge in 1963, although software design was already underway. David Wheeler was in charge of the joint effort between the university and Ferranti. In 1965 the Cambridge side of the team decided to add a

time-sharing In computing, time-sharing is the Concurrency (computer science), concurrent sharing of a computing resource among many tasks or users by giving each Process (computing), task or User (computing), user a small slice of CPU time, processing time. ...

facility for Titan, necessitating the acquisition of additional hardware. When Titan came into full service in 1966, time sharing was available for all staff. Titan was finally switched off in October 1973. Ferranti, by then a division of

International Computers and Tabulators International Computers and Tabulators or ICT was a British computer manufacturer, formed in 1959 by a merger of the British Tabulating Machine Company (BTM) and Powers-Samas. In 1963 it acquired the business computer divisions of Ferranti. It ...

(ICT), marketed the Titan as the Atlas 2. Although intended to be more affordable than the Atlas, its price was still over £1 million. A second Atlas 2 was built in Manchester, and was installed at the Computer-Aided Design Centre ( CADCentre) on Madingley Road together with the Cambridge Titan supervisor. This machine, the last Atlas, was finally switched off on 21 December 1976. A third Atlas 2 was ordered by the UK's Atomic Weapons Research Establishment (AWRE) at

Aldermaston Aldermaston ( ) is a village and civil parish in Berkshire, England. In the 2011 census, the parish had a population of 1,015. The village is in the Kennet Valley and bounds Hampshire to the south. It is approximately from Newbury, Basin ...

. It replaced the faster and much more expensive

IBM 7030 Stretch The IBM 7030, also known as Stretch, was IBM's first transistorized supercomputer. It was the fastest computer in the world from 1961 until the first CDC 6600 became operational in 1964."Designed by Seymour Cray, the CDC 6600 was almost three tim ...

which had been leased from IBM.

Hardware

Titan differed from the original Manchester

Atlas An atlas is a collection of maps; it is typically a bundle of world map, maps of Earth or of a continent or region of Earth. Advances in astronomy have also resulted in atlases of the celestial sphere or of other planets. Atlases have traditio ...

by having a real, but cached,

main memory Computer data storage or digital data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers. The central processin ...

, rather than the paged (or virtual) memory used in the Manchester machine. It initially had 28K of memory, but this was expanded first to 64K and later to 128K. The Titan's main memory had 128K of 48-bit words and was implemented using ferrite core store rather than the part core, part rotating drum-store used on the Manchester Atlas. Titan also had two large hard-disk drives and several magnetic tape decks. As with the Manchester Atlas, it used discrete components, in particular

germanium Germanium is a chemical element; it has Symbol (chemistry), symbol Ge and atomic number 32. It is lustrous, hard-brittle, grayish-white and similar in appearance to silicon. It is a metalloid or a nonmetal in the carbon group that is chemically ...

transistor A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semicondu ...

s. Some of these components can be seen in the online relics collection of the University of Cambridge Computer Laboratory.

Uses

Titan was the computer on which a team from Ferranti based in Bracknell working with David Barron, David Hartley, Roger Needham and Barry Landy of Cambridge University Maths Lab developed the early multi-user

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

called Titan Supervisor. This was arguably the world's first commercially sold

operating system. Other experiments in time-sharing, such as CTSS and

PLATO Plato ( ; Greek language, Greek: , ; born BC, died 348/347 BC) was an ancient Greek philosopher of the Classical Greece, Classical period who is considered a foundational thinker in Western philosophy and an innovator of the writte ...

in the US, were one-of-a-kind research projects. One of Titan's most intensive uses was to compute the inverse

Fourier Transform In mathematics, the Fourier transform (FT) is an integral transform that takes a function as input then outputs another function that describes the extent to which various frequencies are present in the original function. The output of the tr ...

s of data from the One-Mile Radio Telescope.

References

{{DEFAULTSORT:Titan (Computer) 1964 establishments in the United Kingdom 1973 disestablishments in the United Kingdom Ferranti computers History of Cambridge Transistorized computers University of Cambridge Computer Laboratory 20th century in Cambridge