Microsoft's proprietary window system and user interface software released in 1985 to run on top of MS-DOS. Widely criticised for being too slow (hence "Windoze", "Microsloth Windows") on the machines available then. The 1996 market share of operating systems was: DOS/Windows 70% Windows 95 15% Windows NT 2% Other 13% Versions include 1985 Windows 1, 1987 Windows 2, 1987 Windows/386, 1990 Windows 3.0, 1992 Windows 3.1, 1992 Windows for Workgroups 3.1, 1993 Windows 3.11, 1993 Windows for Workgroups 3.11, 1993 Windows NT 3.1, 1994 Windows NT 3.5, 1995 Windows 95, 199? Windows NT 4, 1998 Windows 98, Windows NT 5, Windows XP, Windows 7, Windows 8.