Bill Gates and Paul Allen co-founded Microsoft in 1975 to develop software for microcomputers.
The partnership began after Gates and Allen saw the Altair 8800 featured on the cover of Popular Electronics in January 1975. They contacted its manufacturer, MITS, and demonstrated a version of the BASIC programming language written for the Altair. MITS agreed to distribute it, giving the young company its first major commercial opportunity.
The business was originally styled “Micro-Soft,” a reference to microcomputer software. Gates and Allen later dropped the hyphen, and Microsoft became one of the most influential software companies in the personal-computer era. Its MS-DOS operating system became central to IBM-compatible PCs, while Windows later became its best-known product family.
A common mix-up is crediting Microsoft’s founding only to Gates. Allen was a co-founder and played a key role in creating the Altair BASIC interpreter. Microsoft’s headquarters later moved to the Seattle area, where the company remains closely associated with the technology industry.