Windows XP

Windows XP is a line of operating systems developed by Microsoft for use on personal computers, including home and business desktops, notebook computers, and media centers. The name "XP" stands for eXPerience. Windows XP is the successor to both Windows 2000 Professional and Windows Me, and is the first consumer-oriented operating system produced by Microsoft to be built on the Windows NT kernel and architecture. Windows XP was first released on October 25, 2001, and over 400 million copies were in use in January 2006, according to an estimate in that month by an IDC analyst. It is succeeded by Windows Vista, which was released to volume license customers on November 8, 2006, and worldwide to the general public on January 30, 2007. Direct OEM and retail sales of Windows XP ceased on June 30, 2008, although it is still possible to obtain Windows XP from System Builders until January 31, 2009 or by purchasing Windows Vista Ultimate or Business and then downgrading to Windows XP.

The most common editions of the operating system are Windows XP Home Edition, which is targeted at home users, and Windows XP Professional, which has additional features such as support for Windows Server domains and two physical processors, and is targeted at power users and business clients. Windows XP Media Center Edition has additional multimedia features enhancing the ability to record and watch TV shows, view DVD movies, and listen to music. Windows XP Tablet PC Edition is designed to run ink-aware applications built using the Tablet PC platform. Two separate 64-bit versions of Windows XP were also released, Windows XP 64-bit Edition for IA-64 processors and Windows XP Professional x64 Edition for x86-64.