Real Windows Operating Systems

This is a list of real Windows operating systems actually released by Microsoft.

Pre-NT

 * Windows 1 (1985)
 * Windows 2 (1987)
 * Windows 3 (1990)
 * Windows 3.1 (1992)
 * Windows 95 (4.0, 1995)
 * Windows 98 (4.1, 1998)
 * Windows Millennium Edition (Windows ME, 4.9, 2000)

NT

 * Windows NT 3.1 (1993)
 * Windows NT 3.5 (1994)
 * Windows NT 4 (1996)
 * Windows 2000 (5.0, 2000)
 * Windows XP (5.1, 2001)
 * Windows Vista (6.0, 2006)
 * Windows 7 (6.1, 2009)
 * Windows 8 (6.2, 2012)
 * Windows 8.1 (6.3, 2013)
 * Windows 10 (2015)