Microsoft created Windows and became the first major software company to reach a $1 trillion market capitalization.
Bill Gates and Paul Allen founded Microsoft in 1975. The company initially developed software for the Altair 8800 microcomputer and later supplied the MS-DOS operating system used by IBM-compatible personal computers. Windows became Microsoft’s best-known consumer software platform.
Microsoft’s valuation expanded beyond personal-computer software through products such as Office, enterprise services, Xbox, and Azure cloud computing. It crossed the trillion-dollar market-capitalization mark in 2019, after Apple and Amazon had already reached it.
Market capitalization is not the same as revenue or profit. It represents the stock market’s valuation of all outstanding shares, and it can rise or fall daily even when a company’s products and operations remain unchanged.