Ferranti Mark1.

This Manchester Small-Scale Experimental Machine, nicknamed Baby, was the world's first stored-program computer . It was built for the Victoria University of Manchester by Frederic C. Williams , Tom Kilburn and Geoff Tootill , in addition to ran its first program on 21 June 1948. [38] It was designed as a testbed for the Williams tube the primary random-access digital storage device. [39] Although the computer was considered "small and primitive" because of the standards of its time, it was the first working machine to contain all of the elements essential to a modern electronic computer. [40] As soon as the SSEM had confirmed the feasibility of its design, a project was initiated at the university to develop it in a more usable computer, the Manchester Mark 1 .
The Mark 1 in turn quickly became the prototype with the Ferranti Mark 1 , the world's first commercially available general-purpose computer. [41] Built by Ferranti , ıt had been delivered to the University of Manchester in February 1951. At least seven of most of these later machines were delivered between 1953 and 1957, one of them to Shell labs with Amsterdam . [42] In October 1947, the directors of British catering company J. Lyons & Company thought i would take an active role in promoting the commercial development of computers. The LEO I computer system became operational in April 1951 [43] and ran the world's first regular routine company computer job .