LEOpedia is the LEO Computers Society’s guide to references and holdings related to the story of LEO.

Some items are held at the Centre for Computing History. Other entries simply contain signposts to where the material might be found.

This resource is maintained by Professor Frank Land OBE, with support from CCH as part of our HLF-funded partnership project 'Swiss Rolls, Tea & The Electronic Office: A History of LEO, the World's First Business Computer'.

If any reader knows of any other reference please let Frank Land know at f.land@lse.ac.uk.

You can also view the archive catalogue of the LEO collections held here at the museum:

The LEO Archive comprises material collected by various significant figures from the history of the LEO computer, either in the course of their work for Lyons or gathered later for research. The archive is now on loan to the museum as part of the National Lottery Heritage Funded-project 'Swiss Rolls, Tea and the Electronic Office'. We will also be including in the listings any LEO-related objects from the museum's permanent collection.

The LEO Archive catalogue is a work in progress, so you may find sections which we haven't got to yet - please check back regularly for progress, or get in touch if you have specific questions. 

The archive has been organised into sections by principal collector of the material: David Caminer, Ernest Lenaerts, Frank Land, Peter Bird and the LEO Computers Society. Follow the links below to browse these collections.

The Archive is also available to search by type of material through our LEOPEDIA pages.


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