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.

Released in April of 1987 PC DOS 3.3 which added support for IBM PS/2 and 1.44 MB 3.5-inch floppy disk drives. Another major addition was codepage support for international character sets.

PC DOS 3.3 followed by PC DOS 4.0 in July 1988.