The IBM 701 was annouced internally on 1952-04-29 as "the most advanced, most flexible high-speed computer in the world". Known as the Defense Calculator while in development at IBM Poughkeepsie Laboratory, it went public on 1953-04-07 as the "IBM 701 Electronic Data Processing Machines" (plural because it consisted of eleven connected units).
The 701 was the first IBM large-scale electronic computer manufactured in quantity and their first commercial scientific computer. It was the first IBM machine in which programs were stored in an internal, addressable, electronic memory. It was developed and produced in less than two years from "first pencil on paper" to installation. It was key to IBM's transition from punched card machines to electronic computers.
It consisted of four magnetic tape drives, a magnetic drum memory unit, a cathode-ray tube storage unit, an L-shaped arithmetic and control unit with an operator's panel, a punched card reader, a printer, a card punch and three power units. It performed more than 16,000 additions or subtractions per second, read 12,500 digits a second from tape, print 180 letters or numbers a second and output 400 digits a second from punched-cards.