The generic name for the CPUs and architecture released by IBM
on 1964-04-07. The 360 was marketed as a general purpose computer with 'all round' functionality - hence 360 (degrees).
Models ranged from the 360/20 to the 360/65 and later the 360/95, with typical memory configurations from 16K to 1024K.
Elements of the architecture, such as the basic instruction set
are still in use on IBM mainframes
today. Operating System/360 (OS/360
) was developed for System/360. Other associated operating systems
The 360 architecture was based on an 8-bit byte
, 16 general purpose registers
, 24-bit addressing, and a PSW (Program Status Word) including a location counter. Gene Amdahl
, then an IBM employee, is generally acknowledged as the 360's chief architect. He later went on to found Amdahl Corporaton, a manufacture of PCM mainframe
The 360's predecessors were the smaller IBM 1401 and the large IBM 7090
series. If was followed by the IBM 370
See also ABEND
, Big Red Switch
, mode bit