Bill Gates co-founded Microsoft Corporation in 1975 and turned it into the most popular software company in the world. He dropped out of Harvard to start the company, which initially had little success but broke through with the MS-DOS operating system that made computers easier to use. Gates fought software piracy and built strong defense programs. Today Microsoft is one of the most successful companies, earning billions annually, though it faces criticism for monopolistic practices. Gates is now the richest person in the world and donates over $1 billion per year to charity through his foundation with his wife.