Enigma / Bletchley Park codebreaking (Bombe / Colossus)

Editorial record

Plain-language summary

During the Second World War, British codebreakers built machines to break the German Enigma and Lorenz ciphers by mechanizing the search through vast numbers of possible settings. The Bombe automated the logical elimination of impossible key configurations, while Colossus used electronic valves to process teleprinter traffic at high speed. This work demonstrated that computation could replace human labor on structured reasoning tasks. It also produced engineering experience and people, including Alan Turing, who shaped the first general-purpose computers.