Windows 2000 was a modernization of Windows NT 4.0 which brought many of the desktop changes, including Active Desktop, to Microsoft's Windows NT line. Four editions of Windows 2000 were released, Professional, Server, Advanced Server, Datacenter Server. Improvements over NT 4.0 include new Accessibility Options, increased language and locale support, NTFS 3.0, the Encrypting File System and Active Directory. Windows 2000 was first planned to replace both Windows 98 and Windows NT 4.0 although using the NT kernel for consumer and professional editions would not happen until Windows 2000's successor, Windows XP.
| 1.0 | 2.x | 3.x | NT 3.x | 95 | NT 4.0 | 98 | 2000 | ME | All |