Whirlwind I

Whirlwind I is a vacuum-tube computer developed by the MIT Servomechanisms Laboratory for the U.S. Navy. Operational in 1951, it was among the first digital electronic computers that operated in real-time for output, and the first that was not simply an electronic replacement of older mechanical systems. It was one of the first computers to calculate in bit-parallel (rather than bit-serial), and was the second to use magnetic-core memory after it had been proven to work for some months of use on the Memory Test Computer (MTC). (The MTC received a new core stack later so that some of the work for Whirlwind could instead be done on the MTC. The MTC was a complete, functional computer similar in capability to Whirlwind.) Its development led directly to the Whirlwind II design used as the basis for the United States Air Force SAGE air defense system, and indirectly to almost all business computers and minicomputers in the 1960s, particularly because of the mantra "short word length, speed, people."