DOS 3

DOS 3 or DOS-3 may refer to:
 * Kosmos 557 aka Salyut-3 or DOS-3, a Russian space station
 * Apple DOS for the Apple II series, released in versions 3.1, 3.2, and 3.3
 * Atari DOS 3 for the Atari 8-bit family

It may also refer to versions of the Microsoft MS-DOS family:
 * MS-DOS 3.0, with FAT16 support in 1984
 * MS-DOS 3.1 in 1985
 * MS-DOS 3.2 in 1985
 * MS-DOS 3.21 in 1987
 * MS-DOS 3.21R, a ROMed version of MS-DOS in 1989 for laptops
 * MS-DOS 3.22, a ROMed OEM version of MS-DOS for HP 95LX in 1991
 * MS-DOS 3.25
 * MS-DOS 3.3 in 1987
 * MS-DOS 3.3A
 * Arabic MS-DOS 3.3, a special Arabic version of MS-DOS 3.3 (ADOS) in 1988
 * Hebrew MS-DOS 3.3, a special Hebrew version of MS-DOS 3.3 (HDOS)
 * MS-DOS 3.3R, a ROMed version of MS-DOS in 1990 for TI laptops
 * MS-DOS 3.31, an OEM version of MS-DOS with FAT16B support by Compaq
 * MS-DOS 3.30+,an OEM version of MS-DOS with FAT16B support by Zenith-Data System
 * MS-DOS 3.40, announced OEM version and successor of MS-DOS 3.3 with FAT16B support in 1988

It may also refer to versions of the IBM PC DOS family:
 * PC DOS 3.0, successor of PC DOS 2.11 with FAT16 support in 1984
 * PC DOS 3.1, successor of PC DOS 3.0 in 1984/1985
 * PC DOS 3.2, successor of PC DOS 3.1 in 1986
 * PC DOS 3.21, successor of PC DOS 3.2 in 1986
 * IBM DOS 3.3, successor of PC DOS 3.21 in 1987
 * IBM DOS 3.4, announced successor of IBM DOS 3.3 in 1988

It may also refer to versions of the Digital Research DR DOS family:
 * DR DOS 3.31, based on DOS Plus 2.1 and Concurrent PC DOS 6.0 with FAT16B support in 1988
 * DR DOS 3.32, successor of DR DOS 3.31 in 1988, reporting itself as "PC DOS 3.31"
 * DR DOS 3.33, successor of DR DOS 3.32 in 1988, reporting itself as "PC DOS 3.31"
 * DR DOS 3.34, successor of DR DOS 3.33 in 1988, reporting itself as "PC DOS 3.31"
 * DR DOS 3.35, successor of DR DOS 3.34 in 1988, reporting itself as "PC DOS 3.31"
 * DR DOS 3.40, successor of DR DOS 3.35, reporting itself as "PC DOS 3.31"
 * DR DOS 3.41, successor of DR DOS 3.40 in 1989, reporting itself as "PC DOS 3.31"
 * DR DOS 5.0, successor of DR DOS 3.41 in 1990, reporting itself as "PC DOS 3.31"
 * DR DOS 6.0, successor of DR DOS 5.0 in 1991, reporting itself as "PC DOS 3.31"
 * NetWare PalmDOS 1.0, a successor to DR DOS 6.0 tailored for early palmtop PCs in 1992, reporting itself as "PC DOS 3.31"