The Atanasoff-Berry Computer was the first electronic digital computer.
Built in 1937-1942 at Iowa State University by John V. Atanasoff and Clifford Berry, it introduced the ideas of binary arithmetic, regenerative memory, and logic circuits. These ideas were communicated from Atanasoff to Mauchly, who used them in the design of the better-known ENIAC built several years later.
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