Microsoft

Educated at Lakeside School in Seattle, where he befriended Paul Allen and developed computing interests, he dropped out of Harvard in his junior year to found Microsoft with Allen. At Harvard's Aiken Lab, he developed a BASIC interpreter for the Altair 8800 on a PDP-10 mainframe—Harvard officials were not pleased when they found out—which became the first product of the new company, which they decided to call Micro-Soft. The computer company bought it for $3,000, but Gates kept the copyright. Prior work included Traf-O-Data, a venture using an Intel 8008-based device to analyze traffic patterns, which taught Gates and Allen how to work with early microprocessors and think about technology as a product. Known for his data-driven approach to decision-making, he valued empirical evidence and often relied on data and analysis to guide strategic choices.

Met Bill Gates at Seattle's Lakeside School at age 14, then attended Washington State University for two years before dropping out in 1974 to work as a programmer at Honeywell in Boston. Spotted the January 1975 Popular Electronics cover story on the MITS Altair 8800 and seized the opportunity with Gates to write a BASIC interpreter—despite not owning the hardware. Moved to MITS headquarters in Albuquerque as vice president and software director, then co-founded Microsoft in 1975. Influential in securing the 1980 DOS license and brokering MS-DOS rights for IBM PCs, placing Microsoft at the forefront of the PC boom. Resigned in 1983 after Hodgkin lymphoma diagnosis, remaining on the board until 2000. "At Microsoft, we tried to balance simplicity with power," he wrote in his 2011 memoir—a philosophy reflected in his call for a two-button mouse over Jobs's one-button design.