Windows 2000

Windows 2000 is a major release of the Windows NT operating system developed by Microsoft, targeting the server and business markets. It is the direct successor to Windows NT 4.0, and was released to manufacturing on December 15, 1999, and then to retail on February 17, 2000 for all versions, with Windows 2000 Datacenter Server being released to retail on September 26, 2000.

Windows 2000 introduces NTFS 3.0, Encrypting File System, and basic and dynamic disk storage. Support for people with disabilities is improved over Windows NT 4.0 with a number of new assistive technologies, and Microsoft increased support for different languages and locale information. The Windows 2000 Server family has additional features, most notably the introduction of Active Directory, which in the years following became a widely used directory service in business environments. Although not present in the final release, support for Alpha 64-bit was present in its alpha, beta, and release candidate versions. Its successor, Windows XP, only supports x86, x64 and Itanium processors. Windows 2000 was also the first NT release to drop the "NT" name from its product line.

Four editions of Windows 2000 have been released: ''Professional'', ''Server'', ''Advanced Server'', and ''Datacenter Server''; the latter of which was launched months after the other editions. While each edition of Windows 2000 is targeted at a different market, they share a core set of features, including many system utilities such as the Microsoft Management Console and standard system administration applications.

Microsoft marketed Windows 2000 as the most secure Windows version ever at the time; however, it became the target of a number of high-profile virus attacks such as Code Red and Nimda. Windows 2000 was succeeded by Windows XP a little over a year and a half in October 2001, while Windows 2000 Server was succeeded by Windows Server 2003 more than three years after its initial release on March 2003. For ten years after its release, it continued to receive patches for security vulnerabilities nearly every month until reaching the end of support on July 13, 2010, the same day that support ended for Windows XP SP2.

Both the original Xbox and the Xbox 360 use a modified version of the Windows 2000 kernel as their system software. Its source code was leaked in 2020. Provided by Wikipedia