Windows

In computing, originally Microsoft's graphical user interface (GUI) for IBM personal computers and clones running MS-DOS. Windows has since developed into a family of operating systems that run on a wide variety of computers, from pen-operated palmtop personal digital assistants (PDAs) to large, multiprocessor computers in corporate data centres.

Windows XP Home edition is designed for homes and offices and retains maximum compatibility with programs written for the MS-DOS operating system and earlier versions of Windows. Windows XP Professional edition is designed for business use, especially on workstations and server computers, where it is seen as a rival to Unix and Novell NetWare. Windows CE is a small, modular operating system that supports a subset of the Windows applications programming interface. It is used in PDAs (where it is known as Pocket PC), Windows-Based Terminals (WBTs), and consumer electronics products such as games consoles, DVD players, and television set-top boxes for Internet use. Windows XP Home is limited to Intel and x86-compatible processors but both XP Professional and CE run on a variety of chips from different manufacturers.

Windows XP, called by the company the most important Microsoft product since Windows 95, was released in 2001, promising improved ability to deal with digital multimedia. In 2002, Microsoft released a version of Windows XP to run on the new tablet PC, with advanced handwriting and speech recognition capabilities.

In 2004 the International Data Corporation estimated that 90% of all computer client operating systems were Microsoft Windows, making it by far the most widely used computer operating system.