Acronym for Automatic Computing Engine. An electronic stored-program computer designed in 1945–46 by Alan Turing while he was at the National Physical Laboratory (NPL), near London. The prototype version Pilot ACE was built at the NPL, ran its first program in 1950, and was in full-time use in 1952. The final version was working by 1957. A production model of Pilot Ace, called DEUCE, was marketed by the English Electric company.