Windows 1.0    November 1985
Windows 2.0    December 1987   Xenix 386 appears at the same time
Windows/386    December 1987
Windows 3.0    May 1990
Windows 3.1    April 1992
Windows 95     August 1995
Windows 2000 - Dec 15, 1999
Windows XP     October 2001
Windows Vista  2006
Windows 7  -   October 2009
Windows 8      May 2012
Windows 10     July 2015