IBM 701

(computer)("Defense Calculator") The first of the IBM 700 series of computers.

The IBM 701 was annouced internally on 1952-04-29 as "the mostadvanced, 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 becauseit consisted of eleven connected units).

The 701 was the first IBM large-scale electronic computermanufactured in quantity and their first commercialscientific computer. It was the first IBM machine in whichprograms were stored in an internal, addressable, electronicmemory. It was developed and produced in less than two yearsfrom "first pencil on paper" to installation. It was key toIBM's transition from punched card machines to electroniccomputers.

It consisted of four magnetic tape drives, a magnetic drummemory unit, a cathode-ray tube storage unit, an L-shapedarithmetic and control unit with an operator's panel, apunched card reader, a printer, a card punch and threepower units. It performed more than 16,000 additions orsubtractions per second, read 12,500 digits a second fromtape, print 180 letters or numbers a second and output 400digits a second from punched-cards.

The IBM 701 ran the following languages and systems: BACAIC,BAP, DOUGLAS, DUAL-607, FLOP, GEPURS, JCS-13,KOMPILER, LT-2, PACT I, QUEASY, QUICK, SEESAW,SHACO, SO 2, Speedcoding, SPEEDEX.

IBM History.

IBM 701

IBM's first computer. Introduced in 1952, the 701 was designed for scientific work and research, which led to the development of the FORTRAN programming language. Nineteen machines were built, a record volume for such a computer in that era. Its internal memory contained 2,048 36-bit words of electrostatic memory and 8,192 words of magnetic drum memory (see early memory). The 701 used magnetic tapes for storage and was one of the first machines to use plastic-based magnetic tapes rather than metal. See IBM 650 and IBM 1401.

IBM's First Computer

At General Electric's Aircraft Jet Engine Plant in Evendale, Ohio, this 1954 photo shows GE manager Herbert Grosch explaining the 701 to Ronald Reagan. Reagan was a TV personality for GE at the time. (Image courtesy of IBM.)