Windows 8

Windows 8 is an operating system developed by Microsoft. It replaces Windows 7 and is replaced by Windows 8.1. It reached RTM on 2012-08-01 and was released to general availability on 2012-10-26. Windows 8 was one of the most short-lived builds and it's end of support was in 2016-01-12, as extended support was in favor of Windows 8.1.

Editions
It comes in four main editions: RT, Core, Pro, and Enterprise. All other editions are based on those editions.
 * Windows RT is a special edition of Windows for the ARM architecture. It can only launch Windows Store apps and signed Microsoft desktop applications.
 * Windows 8 (Core) is the lowest available Windows 8 editions.
 * Windows 8 Single Language (CoreSingleLanguage) is the Core edition locked up to only one language.
 * Windows 8 China (CoreCountrySpecific)
 * Windows 8 Pro
 * Windows 8 Pro with Media Center is Pro with Windows Media Center and additional codecs. It can be purchased for existing Windows 8 and Windows 8 Pro users.
 * Windows 8 Enterprise is an edition of Windows 8 for big corporations. It can be activated only by a KMS server. It's the only edition to support creating Windows To Go portable workspaces. It doesn't have Windows Media Center and can't be upgraded to an edition with WMC included.

Media Center
Unlike Windows Vista and Windows 7, Windows Media Center is not included by default in 'any' Windows 8 edition. Customers with existing Windows 8 users can purchase Media Center with the Windows 8 Pro Pack, which includes Windows 8 Pro with Media Center. Customers with existing Windows 8 Pro users can purchase Media Center with the Windows 8 Pro Pack, which was free previously under a promotional offer (till 2013-01-31).

Pre-Milestone 1

 * Note: There has been a debate whether this build is actually a post-RTM build of Windows 7 or an actual Windows 8 alpha.