Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions. Microsoft rose to dominate the home computer operating system market with MS-DOS in the mid-1980s, followed by the Microsoft Windows line of operating systems. 

Microsoft would also come to dominate the office suite market with Microsoft Office. The company has diversified in recent years into the video game industry with the Xbox gaming console as well as into the consumer electronics and digital services market with Zune, MSN and the Windows Phone OS.
  Microsoft Windows is a series of software operating systems and graphical user interfaces produced by Microsoft. Microsoft first introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Microsoft Windows came to dominate the world's personal computer market, overtaking Mac OS, which had been introduced in 1984.    
  Windows Phone is a mobile operating system developed by Microsoft, and is the successor to its Windows Mobile platform. Unlike its predecessor, it is primarily aimed at the consumer market rather than the enterprise market. With Windows Phone 7, Microsoft offers a new user interface with its design language named Metro, integrates the operating system with 3rd party and other Microsoft services, and controls the hardware it runs on.  

Xbox may primarily refer to Microsoft's flagship gaming console, but also referrs to a collection of services which include games, music and video. Xbox Live is an online multiplayer gaming and digital media delivery service. Xbox Music is a digital music that offers music through ad-supported streaming, subscription streaming, and purchase through the Xbox Music Store. Xbox Video is a digital video service developed by Microsoft that offers full HD Movies and TV shows available for rental or purchase in the Xbox Video Store.

The Xbox services are available through the Xbox consolse along with Windows and Windows Phone devices.