Titan was the prototype of the Atlas 2 computer developed by Ferranti

Ferranti

Ferranti or Ferranti International plc was a UK electrical engineering and equipment firm that operated for over a century from 1885 until it went bankrupt in 1993. Known primarily for defence electronics, the Company was once a constituent of the FTSE 100 Index but ceased trading in 1993.The...

 and the University of Cambridge Mathematical Laboratory in Cambridge

Cambridge

The city of Cambridge is a university town and the administrative centre of the county of Cambridgeshire, England. It lies in East Anglia about north of London. Cambridge is at the heart of the high-technology centre known as Silicon Fen – a play on Silicon Valley and the fens surrounding the...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

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

History

Titan differed from the original Manchester Atlas

Atlas Computer (Manchester)

The Atlas Computer was a joint development between the University of Manchester, Ferranti, and Plessey. The first Atlas, installed at Manchester University and officially commissioned in 1962, was one of the world's first supercomputers, considered to be the most powerful computer in the world at...

 by having a real, but cached, main memory, rather than the paged (or virtual) memory

Virtual memory

In computing, virtual memory is a memory management technique developed for multitasking kernels. This technique virtualizes a computer architecture's various forms of computer data storage , allowing a program to be designed as though there is only one kind of memory, "virtual" memory, which...

 used in the Manchester machine. 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

Drum memory

Drum memory is a magnetic data storage device and was an early form of computer memory widely used in the 1950s and into the 1960s, invented by Gustav Tauschek in 1932 in Austria....

 used on the Manchester Atlas. Titan had more memory than the Atlas, but it was slower at 2.5 microseconds access time. 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

Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....

 transistor

Transistor

A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...

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

As a prototype it had a reputation for technical excellence; but it was also often highly unreliable, and indeed some wiring anomalies were still being discovered several years after it was first commissioned.

One of Titan's most intensive uses was to compute the inverse Fourier Transform

Fourier transform

In mathematics, Fourier analysis is a subject area which grew from the study of Fourier series. The subject began with the study of the way general functions may be represented by sums of simpler trigonometric functions...

s of data from the One-Mile Radio Telescope

One-Mile Telescope

The One-Mile Telescope at the Mullard Radio Astronomy Observatory is an array of radio telescopes designed to perform aperture synthesis interferometry.- History :The One Mile Telescope was completed by the Radio Astronomy Group of Cambridge...

.

Titan was the computer on which Peter Swinnerton-Dyer

Peter Swinnerton-Dyer

Sir Henry Peter Francis Swinnerton-Dyer, 16th Baronet KBE FRS , commonly known as Peter Swinnerton-Dyer, is an English mathematician specialising in number theory at University of Cambridge...

 developed the early multi-user time-sharing

Time-sharing

Time-sharing is the sharing of a computing resource among many users by means of multiprogramming and multi-tasking. Its introduction in the 1960s, and emergence as the prominent model of computing in the 1970s, represents a major technological shift in the history of computing.By allowing a large...

 operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

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

Time-sharing

Time-sharing is the sharing of a computing resource among many users by means of multiprogramming and multi-tasking. Its introduction in the 1960s, and emergence as the prominent model of computing in the 1970s, represents a major technological shift in the history of computing.By allowing a large...

 operating system. Other experiments in timesharing, such as CTSS and PLATO in the US were one-of-a-kind research projects.

Ferranti, by then a division of International Computers and Tabulators

International Computers and Tabulators

International Computers and Tabulators or ICT was formed in 1959 by a merger of the British Tabulating Machine Company and Powers-Samas. In 1963 it also added the business computer divisions of Ferranti...

 (ICT), marketed the Titan as the Atlas 2.
Although intended to be more affordable than the Atlas, its price was still over £

Pound sterling

The pound sterling , commonly called the pound, is the official currency of the United Kingdom, its Crown Dependencies and the British Overseas Territories of South Georgia and the South Sandwich Islands, British Antarctic Territory and Tristan da Cunha. It is subdivided into 100 pence...

1 million.
A second Atlas 2 was built, also in Cambridge, and was installed at the Computer-Aided Design Centre (CADCentre) on Madingley Road

Madingley Road

Madingley Road is a major arterial road linking central Cambridge, England with Junction 13 of the M11 motorway. It passes by West Cambridge, a major new site where some University of Cambridge departments are being relocated....

. 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

Atomic Weapons Establishment

The Atomic Weapons Establishment is responsible for the design, manufacture and support of warheads for the United Kingdom's nuclear deterrent. AWE plc is responsible for the day-to-day operations of AWE...

 at Aldermaston

Aldermaston

Aldermaston is a rural village, civil parish and electoral ward in Berkshire, South-East England. In the 2001 United Kingdom Census, the parish had a population of 927. The village is on the southern edge of the River Kennet flood plain, near the Hampshire county boundary...

. It replaced the faster but much more expensive IBM 7030 Stretch which had been leased from IBM.