Windows operating system

Microsoft Windows

Screenshot of Windows 10 (Creators Update, version 1703), showing the Action Center and Start Menu
Developer	Microsoft
Source model	Closed / shared source
Initial release	November 20, 1985; 31 years ago (1985-11-20), as Windows 1.0
Latest release	1703 (10.0.15063.483) (July 11, 2017; 6 days ago (2017-07-11))
Latest preview	RS3 (10.0.16237.1000) (July 7, 2017; 10 days ago (2017-07-07))
Marketing target	Personal computing
Available in	137 languages
Update method	Windows Update Windows Anytime Upgrade Windows Store WSUS
Package manager	Windows Installer (.msi), Windows Store (.appx)
Platforms	ARM, IA-32, Itanium, x86-64, DEC Alpha, MIPS, PowerPC
Kernel type	Windows NT family: Hybrid Windows CE: Hybrid Windows 9x and earlier: Monolithic (MS-DOS)
Default user interface	Windows shell
License	Proprietary commercial software
Official website	windows.microsoft.com

Microsoft Windows, or simply Windows, is a metafamily of graphical operating systems developed, marketed, and sold by Microsoft. It consists of several families of operating systems, each of which cater to a certain sector of the computing industry with the OS typically associated with IBM PC compatible architecture. Active Windows families include Windows NT and Windows Embedded; these may encompass subfamilies, e.g. Windows Embedded Compact (Windows CE) or Windows Server. Defunct Windows families include Windows 9x, Windows Mobile and Windows Phone.

Microsoft introduced an operating environment named Windows on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Microsoft Windows came to dominate the world's personal computer (PC) market with over 90% market share, overtaking Mac OS, which had been introduced in 1984. Apple came to see Windows as an unfair encroachment on their innovation in GUI development as implemented on products such as the Lisa and Macintosh (eventually settled in court in Microsoft's favor in 1993). On PCs, Windows is still the most popular operating system. However, in 2014, Microsoft admitted losing the majority of the overall operating system market to Android, because of the massive growth in sales of Android smartphones. In 2014, the number of Windows devices sold was less than 25% that of Android devices sold. This comparison however may not be fully relevant, as the two operating systems traditionally target different platforms.