The 7AK7 is a pentode vacuum tube (thermionic valve). According to its manufacturer, Sylvania, it was "designed for service in electronic computers".Sylvania. Engineering Data Service. 7AK7. July 1953.
The tube was developed in 1948, designed at the request of L. D. Wilson for use in the Whirlwind computer. Significant attention was directed towards its manufacturing process in order to ensure the part's reliability.David R. Brown, T. F. Clough, and P. Youtz. Investigation of 7AK7 Processing, Emporium, Pa., March 2, 1948. URI: http://hdl.handle.net/1721.3/38986 Dubbed the "computer tube", it became a popular tube for computers for a while. IBM, however, switched to more compact miniature tubes, starting with the IBM 604 in 1948.
See also 5965, a triode developed for early digital computers 25L6, a tetrode found in early computers
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