Microsoft Windows is a group of several graphical operating system families, all of which are developed, marketed, and sold by Microsoft . Each family caters to a certain sector of the computing
industry . 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
of the massive growth in sales of Android