Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base as of 2011. The name "XP" is short for "eXPerience", highlighting the enhanced user experience.
Windows XP, the successor to Windows 2000 and Windows ME, was the first consumer-oriented operating system produced by Microsoft to be built on the Windows NT kernel. Windows XP was released worldwide for retail sale on October 25, 2001, and over 400 million copies were in use in January 2006. It was succeeded by Windows Vista in January 2007. Direct OEM and retail sales of Windows XP ceased on June 30, 2008. Microsoft continued to sell Windows XP through their System Builders (smaller OEMs who sell assembled computers) program until January 31, 2009. On April 10, 2012, Microsoft reaffirmed that extended support for Windows XP and Office 2003 would end on April 8, 2014 and suggested that administrators begin preparing to migrate to a newer OS. But on January 17, 2014 Microsoft confirmed that Monthly Microsoft's Malicious Software Removal Tool (MSRT) which aligned with Microsoft's anti-malware engines and signature still available until July 14, 2015. XP users can download the software from its website manually.
The NT-based versions of Windows, which are programmed in C, C++, and assembly, are known for their improved stability and efficiency over the 9x versions of Microsoft Windows. Windows XP presented a significantly redesigned graphical user interface, a change Microsoft promoted as more user-friendly than previous versions of Windows. In an attempt to further ameliorate the "DLL hell" that plagued the past versions of Windows, improved side-by-side assembly technology in Windows XP allows side-by-side installation, registration and servicing of multiple versions of globally shared software components in full isolation. It is also the first version of Windows to use product activation in an effort to reduce software piracy.
During Windows XP's development, the project was codenamed "Whistler", after Whistler, British Columbia, as many Microsoft employees skied at the Whistler-Blackcomb ski resort.
According to web analytics data generated by Net Applications,
Windows XP was the most widely used operating system until August 2012, when
Windows 7 overtook it. As of February 2014, Windows XP market share is at
29.23%, having decreased almost every month since November 2007 until February
2014, the first month for which statistics are publicly available from Net
While retaining some similarities to previous versions, Windows XP's interface was overhauled with a new visual appearance, with an increased use of alpha compositing effects, drop shadows, and "visual styles", which completely change the appearance of the operating system. The amount of effects enabled are determined by the operating system by the computer's processing power, and can be enabled or disabled on a case-by-case basis. XP also added ClearType, a new subpixel rendering system designed to improve the appearance of fonts on LCD displays. A new set of system icons were also introduced. The default wallpaper, Bliss, is a photo of a landscape in the Napa Valley outside Napa, California, with rolling green hills and a blue sky with stratocumulus and cirrus clouds.
The Start menu received its first major overhaul on XP,
switching to a two-column layout with the ability to list pin and display
frequently used applications, recently opened documents, and the traditional
cascading "All Programs" menu. The taskbar can now group windows
opened by a single application into one taskbar button, with a popup menu
listing the individual windows. The notification area also hides
"inactive" icons by default. The taskbar can also be
"locked" to prevent accidental moving or other changes. A "common
tasks" list was added Windows Explorer's sidebar was updated to use a new
task-based designs with lists of common actions; the tasks displayed are
contextually relevant to the type of content in a folder (i.e. a folder with
music displays offers to play all the files in the folder, or burn them to a
Microsoft has provided support for Windows XP for the past 12 years. But now the time has come for us, along with our hardware and software partners, to invest our resources toward supporting more recent technologies so that we can continue to deliver great new experiences.
As a result, after April 8, 2014, technical assistance for Windows XP will no longer be available, including automatic updates that help protect your PC. Microsoft will also stop providing Microsoft Security Essentials for download on Windows XP on this date. (If you already have Microsoft Security Essentials installed, you will continue to receive anti-malware signature updates for a limited time, but this does not mean that your PC will be secure because Microsoft will no longer be providing security updates to protect your PC.)
If you continue to use Windows XP after support ends, your computer will still work but it might become more vulnerable to security risks and viruses. Also, as more software and hardware manufacturers continue to optimize for more recent versions of Windows, you can expect to encounter greater numbers of apps and devices that do not work with Windows XP.