Welcome to LEO, the first business computer

This is the home of Swiss Rolls, Tea and the Electronic Office, our lottery funded project on LEO Computers.

In the late 1940s, J. Lyons and Co., the country’s largest caterer, made the prescient decision to invest in the computer developments being made at Cambridge University (EDSAC) and from this collaboration came the Lyons Electronic Office (LEO), the world’s first business computer.

LEO computers played a key role in the early development of computing, and its subsequent social impact, but the LEO story is not well known.

So, in partnership with the LEO Computers Society, we are preserving, archiving and digitising LEO artefacts, documents and personal memories before they are lost forever. Then, using a variety of approaches to ensure the accessibility of the new archive, for example cutting-edge virtual reality techniques, we are raising public awareness and pride in this important, uniquely British heritage.

Find out more about the LEO Collections

To keep updated on our progress, visit our blog

Browse the LEO Collections by Subject

With this project, we are making safe internationally significant, historically important artefacts relating to the early Lyons Electronic Office (LEO) computers. The LEO story is uniquely British, it pre-dates computing as we know it today and it straddles both computing history and British social history in its links with the Lyons teashops, prominent on high streets in the first half of the 20th century.

Amongst the artefacts that will tell these stories are:

1. Documents (correspondence, reports, photographs, schematics) recording technical developments in the early years of computing and their application to the business world and beyond. They focus on LEO but encompass/review many other early systems and, as LEO grew out of catering company Lyons, they incorporate important social heritage.

2. Computer hardware, magnetic tapes and 'software' from the 1950s on. No LEO computers remain in the world today but bringing fragments that are privately held together with the documentation will offer important detail about the birth, scale and impact of these machines.

3. Knowledge and stories. The LEO Computers Society has a membership of former LEO employees and enthusiasts, mostly older people whose memories of early business computing is being shared with subsequent generations through oral history interviews.

View our timeline of the development of the LEO computers.

The LEO Computers story will be one of the ways in which CCH bridges the gap between the past, the present and our joint future.


A key part of the project is developing the Leopedia, a hub for all things LEO. Here we bring together sources of information on LEO, including both material that is held here at CCH but also pointing to material held in other institutions or published in books, journals or using other media.
Documentation and photos that are digitised as part of this project are also listed within Leopedia.

A partnership project:

Help support the museum by buying from the museum shop

View all items

Founding Sponsors
redgate Google ARM Real VNC Microsoft Research
Heritage Lottery Funded
Heritage Lottery Fund
Accredited Museum