Microsoft DOS History

1981	MS-DOS 1.0 was released August, 1981.
1982	MS-DOS 1.25 was released August, 1982.
1983	MS-DOS 2.0 was released March, 1983.
1984	Microsoft introduces MS-DOS 3.0 for the IBM PC AT and MS-DOS 3.1 for networks.
1986	MS-DOS 3.2 was released April, 1986.
1987	MS-DOS 3.3 was released April, 1987.
1988	MS-DOS 4.0 was released July, 1988.
1988	MS-DOS 4.01 was released November, 1988.
1991	MS-DOS 5.0 was released June, 1991.
1993	MS-DOS 6.0 was released August, 1993.
1993	MS-DOS 6.2 was released November, 1993
1994	MS-DOS 6.21 was released March, 1994
1994	MS-DOS 6.22 was released April, 1994