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This is the site of the LEO Computers Society celebrating the World's first business computer.
Membership of the Society is open to:
  • all ex-employees of LEO Computers and its succeeding companies;
  • anyone who worked with a LEO computer;
  • and anyone who has a specific interest in the history of LEO Computers.
We encourage those who have an interest in LEO, as specified above, to join the Society
- see the Application Form.     Membership is currently free of charge.

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In October 1947, the directors of J. Lyons & Company, a British catering company famous for its teashops but with strong interests in new office management techniques, decided to take an active role in promoting the commercial development of computers and build their own digital computer.
In 1951 the LEO I computer was operational and ran
the world's first regular routine office computer job.

The company LEO Computers Ltd was formed in 1954 and went on to build Leo II and Leo III computers.
LEO II computers were installed in many British offices, including Ford Motor Company, British Oxygen Company and the 'clerical factory' of the Ministry of Pensions & National Insurance at Newcastle. LEO lll computers were installed in Customs & Excise, Inland Revenue, The Post Office and in Australia, South Africa and Czechoslovakia.
LEO Computers Ltd merged with the computer interests of English Electric in 1963 to form English Electric LEO, and later, English Electric Leo Marconi (EELM). Subsequent mergers eventually found LEO incorporated into ICL in 1968, whilst the Bureau operation, based at Hartree House, combined with Barclays to form Baric.
See the The Wikipedia LEO entry for more information about Leo Computers.
A comprehensive collection of references and holdings related to the story of LEO has been compiled by Frank Land, FBCS.   Now known as the LEOPEDIA and currently at 49 pages, it is regularly augmented. The areas covered are shown below in a clip from the Contents page of the LEOPEDIA. The latest PDF version (17/11/2017) is available here...