The British LEO I (Lyons Electronic Office I) computer, ran its first business application in 1951. The computer, modeled closely on the Cambridge EDSAC, was the first computer in the world that was used for commercial business applications.

Origins and initial design

J. Lyons and Co., one of the UK's leading catering and food manufacturing companies in the first half of the 20th century, sent two of its senior managers to the USA in 1947 to look at new business methods developed during the Second World War. During their visit they came across digital computers then used exclusively for engineering and mathematical computations. They saw the potential of computers to help solve the problem of administering a major business enterprise. They also learned that Cambridge University, back in the UK, was actually building such a machine, the pioneering EDSAC computer.

On their return to company headquarters in London they published a recommendation to the Lyons' Board that Lyons should acquire or build a computer to meet their business needs. This was accepted, and it was agreed that Cambridge University should receive some financial support if Cambridge gave some help to the Lyons' initiatve.

Cambridge provided training and support for the Lyons' engineers. By 1949 they had the basics of a computer specifically designed for business data processing running and in November 1951 rolled out the world's first commercial business application. The computer was called the LEO - Lyons Electronic Office.

Technical description

LEO I's clock speed was 500 kHz, with most instructions taking about 1500 ms to execute. To be useful for business applications the computer had to be able to handle a number of data streams, input and output simultanously. Hence its chief designer, Dr John Pinkerton, designed the machine to have multiple input/output buffers. In the first instance these were linked to fast paper tape readers and punches, fast punched card readers and punches, and a 100 line a minute tabulator. Later other devices including magnetic tape were added. Its ultrasonic delay line memory based on tanks of mercury, with 2K (2048) 35-bit words (i.e., 4¾ K bytes), was four times as large as EDSACs.

Applications; Successors

Lyons used LEO I initially for valuation jobs, but its role was extended to include payroll, inventory, and so on. One of LEO I 's early tasks was the elaboration of daily orders which were phoned in every afternoon by their shops and used to calculate the overnight production requirements, assembly instructions, delivery schedules, invoices, costings and management reports. This, arguably, could be the first instance of an integrated management information system plus a computerised call center. The LEO project were also pioneers in outsourcing – in 1956 they started doing the payroll calculations for Ford UK and others on the LEO I machine. The success of this led to the company dedicating one of its LEO II machines to bureau services.

In 1954, with the decision to proceed with LEO II and interest from other commercial companies, Lyons formed LEO Computers Ltd. In 1963 it was taken over by English Electric and this led to the breaking up of the team that had inspired LEO computers. English Electric went on to build the LEO III designed by the LEO team before the takeover and subsequently the faster LEO 36O andLEO 326 models. These allowed concurrent running of application programmes through the Master programme operating system. Some were still in commercial use until 1981. English Electric LEO Computers Ltd eventually merged with others to become in 1968 ICL.

References

• Bird, P. J. (1994). LEO: The First Business Computer. Wokingham: Hasler Publishing Co.
• Caminer, D.T., Aris, J.B,, Hermon, P.M., Land, F.F. (1997). LEO: The Incredible Story of the World’s First Business Computer. New York, NY: McGraw-Hill.
• Ferry, G. (2003). A computer called LEO. Hammersmith: Harper Perennial.

External links

• "About LEO". From Business Computing: the Second 50 Years, The Guildhall conference for business leaders, 2001.
• LEO Computers Society
  • Record of LEO II installations
  • Record of LEO III installations