Disk Operating System

(operating system)   (DOS) The original disk operating system from IBM.

DOS was the low-end OS of choice on the IBM 360, the high-end system was called just "OS". DOS had a smaller kernel and less functionality than OS and could run on the typical 32K 360/30 and 64K 360/40 class machines.

DOS was a successor to TOS.

Last updated: 1999-01-20