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Harvard Mark I

Harvard Mark I The name given at Harvard University to the Automatic Sequence Controlled Calculator (ASCC), an electromechanical computer based on the ideas of Harvard's Howard H. Aiken. This machine, which performed calculations using rotating shafts, gears, and cams, following a sequence of instructions on paper tape, was started in 1937; it was financed by IBM, built in collaboration with IBM engineers at their laboratories in Massachusetts, and became operational at Harvard in 1944. It was donated by IBM to Harvard later that year. The Mark I was used by the US navy for ballistics and ship design. Aiken's Harvard Mark II, based on electrical relays, was operational in Sept. 1948.

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