Microsoft developed Windows and launched its first major stock-market offering in 1986.
Microsoft was founded in 1975 by Bill Gates and Paul Allen. The company initially focused on programming languages and software for early microcomputers, including a version of BASIC for the Altair 8800. Its partnership with IBM helped make MS-DOS a major personal-computer operating system.
Microsoft went public on March 13, 1986. Windows later became the company’s best-known consumer software platform, while Office became a dominant productivity suite. Microsoft also built businesses around enterprise servers, cloud computing, gaming, search, and professional networking.
The company’s market capitalization reflects investors’ valuation of its publicly traded shares. It is not the same as Microsoft’s cash balance or the value of all software installed on customers’ computers.