IBM 700/7000 series

IBM 700/7000 series

An IBM 704 mainframe at NACA in 1957
Type	Mainframe/ scientific computer
Release date	1953; 71 years ago (1953)
Successor	IBM 8000 (not released) IBM System/360
Related	IBM 1400 series

The IBM 700/7000 series is a series of large-scale (mainframe) computer systems that were made by IBM through the 1950s and early 1960s. The series includes several different, incompatible processor architectures. The 700s use vacuum-tube logic and were made obsolete by the introduction of the transistorized 7000s. The 7000s, in turn, were eventually replaced with System/360, which was announced in 1964. However the 360/65, the first 360 powerful enough to replace 7000s, did not become available until November 1965. Early problems with OS/360 and the high cost of converting software kept many 7000s in service for years afterward.