Windows is the operating system that most home and business users will be familiar with as it comes installed on most pc’s or laptops at the point of purchase. Windows as an operating system has gone through a number of revisions from windows 1 to the current windows 7 and Windows 8 is currently in beta testing phase. The full list is
Domestic or home user versions : Windows 1.0, 2.0, 3.0, 3.1, 3.11 for workgroups, windows 95(4), windows 98(5), windows 98se(updated release of windows 5), Windows me(updated release of windows 5), Windows Neptune( never officially released built on windows 2000 core), Windows XP(windows 6), Windows Vista(7), Windows 7(based on Vista core),Windows 8, Windows 8.1) and the soon to be released Windows 10
Business users(NT family) : NT 3.1, NT 3.5, NT 4.0, Windows 2000. After Windows 2000 came Windows Xp in both domestic and commercial versions and the domestic and business lines were merged into one.
All operating systems from XP onwards are based on an NT core so technically Windows XP is NT 5, Windows Vista is NT 6 and Windows 7 is NT 6.1.
There have also been a number of server operating systems for business with a number of version of each namely windows 2000 server(2000 core), Server 2003(xp core), server 2003 R2(xp core updated), Server 2008( Vista core), Server 2008 R2(based on windows 7 i.e. updated Vista core), Server 2011( Server 2008 R2 with additional software and services) and home server versions based on xp and windows 7.Server 2012 is based on Windows 8 and Server 2012 R” on Windows 8.1
Windows ce: This was released as a cut down version of windows specifically for mobile devices, pretty much superceeded now with windows 7 mobile.