Coordinates: 47°38′22.55″N 122°7′42.42″W / 47.6395972°N 122.12845°W / 47.6395972; -122.12845

Microsoft Corporation (NASDAQ: MSFT) is an American multinational corporation headquartered in Redmond, Washington, United States that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions. Established on April 4, 1975 to develop and sell BASIC interpreters for the Altair 8800, 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 is one of the largest software corporations in the world.

Microsoft would also come to dominate the office suite market with Microsoft Office. The company has diversified into the video game industry with the Xbox and Xbox 360 consoles and the consumer electronics and digital services market MSN, the Zune and the Windows Phone OS. The ensuing rise of stock in the company's 1986 initial public offering (IPO) made an estimated three billionaires and 12,000 millionaires from Microsoft employees (Forbes 400 list revealed that in March 2011 both Jon Shipley and Nathan Myhrvold lost their billionaire status). In May 2011, Microsoft Corporation acquired Skype Communications for $8.5 billion.

Steven Anthony "Steve" Ballmer (born March 24, 1956) is the chief executive officer of Microsoft, having held that post since January 2000. As of 2012^[update], his personal wealth is estimated at $15.7 billion, ranking number 19 on the Forbes 400.

Ballmer was born in Detroit, Michigan to a Swiss American father and a Jewish American mother. He grew up in the community of Farmington Hills, Michigan. In 1973, he attended college prep and engineering classes at Lawrence Technological University and graduated from Detroit Country Day School, a private college preparatory school in Beverly Hills, Michigan, with a perfect score of 800 on the mathematical section of the SAT. He now sits on the school's board of directors. In 1977, he graduated magna cum laude from Harvard University with a A.B. in mathematics and economics.

At college, Ballmer managed the football team, worked on The Harvard Crimson newspaper as well as the Harvard Advocate, and lived down the hall from fellow sophomore Bill Gates. He then worked for two years as an assistant product manager at Procter & Gamble, where he shared an office with Jeffrey R. Immelt, who later became CEO of General Electric. In 1980, he dropped out of the Stanford Graduate School of Business to join Microsoft.