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A computer that represents numbers and other data using discrete internal states, in contrast to the continuously varying quantities used in an analog computer.
Some of the fundamental ideas behind the digital computer were proposed by Alan Turing between 1936 and 1938. The design of the Atanasoff-Berry Computer (1937-1942) included some of the important implementation details but the first digital computer to successfully run real programs was the Z3 (1941). ENIAC (1943-1946) was the first electronic digital computer but was only programmable by manual rewiring or switches.