Although today MS-DOS resides primarily in the archives, for over 15 years Microsoft had developed and improved its now relic, yet classic operating environment.
 

Date Product Name 12 Aug 1981 MS-DOS 1.0 May 1982 MS-DOS 1.1 Jun 1982 MS-DOS 1.24 Jul 1982 MS-DOS 1.25 Mar 1983 MS-DOS 2.0 May 1983 MS-DOS 2.01 Mar 1984 MS-DOS 2.1 Mar 1984 MS-DOS 2.11 Aug 1984 MS-DOS 3.0 Nov 1984 MS-DOS 3.1 Jan 1986 MS-DOS 3.2 Jan 1986 MS-DOS 3.25

Date Product Name Aug 1987 MS-DOS 3.3 Nov 1987 MS-DOS 3.31 Jun 1988 MS-DOS 4.0 Nov 1988 MS-DOS 4.01 Jun 1991 MS-DOS 5.0 1992 MS-DOS 5.0a 30 Mar 1993 MS-DOS 6.0 Nov 1993 MS-DOS 6.2 2 Mar 1994 MS-DOS 6.21 11 Apr 1994 MS-DOS 6.22 24 Aug 1995 MS-DOS 7.0 Aug 1996 MS-DOS 7.1