IBM PC DOS is a DOS system for the IBM Personal
Computer and compatibles, manufactured and sold
by IBM from the 1980s to the 2000s.
In March of 1983 IBM released PC DOS 2.0 to
support IBM Personal Computer XT. The new OS had
support for double sided floppy disks and hard
drives up to 10MB. PC DOS came on two 180 kB
5.25-inch disks or one double-sided 360 kB 5.25
inch floppy disk.
PC DOS 2.0 was updated to version 2.1 in October