A mathematician's machine cracked Enigma and may have shortened WWII by years

At Bletchley Park, Alan Turing designed the Bombe, an electromechanical machine that automated the search for the daily settings of Germany's Enigma cipher. Decrypted German communications, codenamed Ultra, gave Allied commanders intelligence on U-boat positions and troop movements throughout the war. Historians estimate the codebreaking shortened the war in Europe by roughly two to four years, saving millions of lives.

— Andrew Hodges, Alan Turing: The Enigma — 1983; definitive biography covering Turing's Bletchley Park work
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