Windows XPIn 2001, Microsoft introduced Windows XP (codenamed "Whistler"). The merger of the Windows NT/2000 and Windows 95/98/Me ranges was achieved with Windows XP. Windows XP uses the Windows NT 5.1 kernel, marking the entry of the Windows NT kernel into the mainstream market, to replace the aging 16/32-bit branch. Windows XP is the longest version of Windows ever released between upgrades, from 2001 to 2007, when Windows Vista was released to consumers. The Windows XP line of operating systems was surpassed by Windows Vista on January 30, 2007. Windows XP is available in a number of versions: • "Windows XP Home Edition", for desktop and portable computers (notebooks) • "Windows XP Home Edition N", as above, but without default installation of Windows Media Player, as required by a European Union decision • "Windows XP Professional", for professional and experienced users • " Windows XP Professional N", as above, but without default installation of Windows Media Player, as required by a decision of the European Union • Windows XP Media Center Edition (MCE), launched in November 2002 for computers desktop and laptop computers with a focus on home entertainmento Windows XP Media Center Edition 2003o Windows XP Media Center Edition 2004o Windows XP Media Center Edition 2005, released October 12, 2004. • "Windows XP Tablet PC Edition", for tablets PC (PC with touch screens)o Windows XP Tablet PC Edition 2005• Windows XP Embedded, for embedded systems• "Windows XP Starter Edition", for new computer users in developing countries• Windows XP Professional x64 Edition, released April 25, 2005 for home and workstation systems using 64-bit processors based on the x86-64 instruction set (AMD calls it AMD64, Intel calls it Intel 64) • Windows XP 64-bit Edition, is a version for the Intel Itanium processor line; maintains 32-bit compatibility only through a software emulator. Its functionality is roughly analogous to that of Windows XP Professional. It was discontinued in September 2005 when the last workstation vendor Itanium stopped shipping Itanium systems marketed as "Workstations". o Windows XP 64-bit Edition 2003, based on the Windows NT 5.2 code base. Windows XP has many features not found in previous versions. of Windows. Windows XP provides new and/or improved drivers and user interfaces for devices compared to Windows Me and 98. On older versions of Windows, when users upgrade a device driver, it is possible that the new driver is less efficient or functional than the original. Reinstalling the old driver can be very complicated and to avoid this dilemma, Windows XP keeps a copy of an old driver when a new version is installed..