Windows XP

Windows XP (originally code-named Whistler) is the latest version of the Windows operating system from the Microsoft Corporation. It was made publicly available on October 25, 2001. Microsoft initially released two versions: Home and Professional. Home is targeted at home users, while Professional has additional features designed for businesses such as network authentication and dual-processor support. The letters "XP" originate from the word experience.

Before XP, Microsoft produced two separate lines of operating systems. One line, represented by Windows 95, Windows 98 and Windows Me was designed for home desktop computers, while the other line, represented by Windows NT and Windows 2000, was aimed at the corporate and professional market, and also included special server versions. Windows XP is Microsoft's attempt to offer a single operating system for all purposes, at the cost of finally deciding to remove support for DOS-based programs from the new operating system.

Windows XP is based on the Windows 2000 code with a newly developed Graphical User Interface (called Luna), which includes slightly redesigned features, some of which appear to have been inspired by modern Linux desktop environments such as KDE. The graphical login screen with user images is one example. In addition, Windows XP ushered in Microsoft's new "task-based" UI featuring sidebars with access to task-specific functions; marking a shift from the desktop-metaphor used in Mac OS X and most distributions of Linux. However, critics argue that the task-based design only adds visual clutter; as it offers no new functionality over simpler toolbars commonly found in operating systems using the desktop metaphors. The additional processing overhead is substantial.

It includes a simplified set of the user security features of Windows 2000 and an integrated firewall which was part of a major new effort to secure Microsoft products following a very long history of security issues and vulnerabilities.

XP has come under intense criticism and scrutiny due to the integration of many user applications for which there has traditionally been a thriving third-party market, such as firewalls, media players (Windows Media Player), instant messengers (Windows Messenger), as well as its close tying to the Microsoft Passport network service, which is seen by many computer experts as a security risk and a potential threat to privacy. These features are also widely believed to be a continuance of Microsoft's traditional anticompetitive behavior.

It has also been sharply criticized for its product activation[?] scheme. This takes an audit of certain components on the host computer, creating a unique reference number that is logged by Microsoft before the software can be used permanently (it comes with a 30 day activation period). Installing the software on another computer, or merely changing certain hardware components such as the network card, generates a different number that does not match the one stored by Microsoft, thus preventing a new license being issued, and disabling the software.

In November 2002, Microsoft released two new versions of XP for specific hardware:

• Windows XP Media Center Edition for special PC's. Currently, these PC's are the HP Media Center Computer, and the Alienware Navigator series. Windows XP Media Center Edition must be bundled with one of these computers, and cannot be bought in stores.
• Windows XP Tablet PC Edition for specially designed notebook/laptop computers with a touch-sensitive screen supporting handwritten notes and portrait-oriented screens.

Additionally on March 28, 2003, Microsoft released another version:

• Windows XP 64 Bit Edition for manufacturers to install on computers with Intel Itanium 2 processors.

See also: History of Microsoft Windows.