Validity and Correctness in LEO I and II

Abstract of the presentation at the roundtable What is a (computer) program? at the prelaunch of the project PROGRAMme in Paris, at the CNAM – Conservatoire national des arts et m├ętiers, on the 20th of October 2017.

The presentation is an historical reconstruction of the procedures to ensure validity and program correctness in the early examples of business computers: the focus of the talk is the hardware testing, data validation and program correctness techniques designed for LEO I and II in the UK during the 1950s. Continue reading “Validity and Correctness in LEO I and II”

Celebration of LEO I’s first routine job

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LEO I (Lyons Electronic Office). Source: Modern Records Centre, University of Warwick

On November 29th, 2016 LEO Computer Society will unveil a plaque commemorating LEO I on the 65th anniversary of its first business routine run in Lyons Walk, Olympia, London. The location is close to the former location of Cadby Hall, the major office and factory complex in Hammersmith, London, which was the headquarters of J. Lyons & Co and LEO’s first home.