The operating system
announced by IBM
at the low end for the System/360
in 1964 and delivered in 1965 or 1966.
Following the failure of OS
, IBM designed DOS for the low end machines, able to run in 16KB(?) and 64KB memory.
DOS/360 used three memory partitions, but it had no serious memory protection
. The three partitions were not specialised, but frequently one was used for spooling punched cards
, another one for batch job execution and another for spooling disk to printers.
With DOS/VS, introduced in 1970, the number of partitions was increased, virtual memory
was introduced and the minimum memory requirements increased.
Later they released DOS/VSE and ESA/VSE. DOS/360 successors are still alive today (1997) though not as popular as in the late 1960s.
Contrary to the Hacker's Jargon File
was not copied from DOS/360.