Bletchley Park Codebreaking Machines

Bletchley Park Codebreaking Machines are the pair of purpose-built computing devices, the Bombe and the Colossus computer, that British codebreakers used at Bletchley Park to attack German cipher traffic during the Second World War. The bombe was an electromechanical device, developed from a Polish design and refined by Alan Turing and Gordon Welchman, that discovered the daily settings of the Enigma machines used across the German military's radio networks by testing possible rotor positions at high speed. Colossus, built later in the war to attack the more complex Lorenz cipher used for high-level German communications, first worked in December 1943 and began operational use at Bletchley Park in February 1944; it is recognized as the world's first programmable digital electronic computer. Together the two machines turned codebreaking from a slow manual craft into a mechanized, then electronic, production process, and their wartime work is credited with shortening the war by giving Allied commanders early access to German operational plans.