Bill Gates

Skinny, shy and awkward, teenaged Bill Gates seemed an unlikely successor to his overachieving parents. His father, powerfully built and 6'6'' tall, was a prominent Seattle attorney, and his gregarious mother served on charitable boards and ran the United Way. While he showed enormous talent for math and logic, young Bill, a middle child, was no one's idea of a natural leader, let alone a future billionaire who would reinvent American business.

Born in 1955, Gates attended public elementary school, and enrolled in the private Lakeside School at age 12. The following year, Gates wrote his first computer program, at a time when computers were still room-sized machines run by scientists in white coats. Soon afterwards, he and his friend Paul Allen wrote a scheduling program for the school—which coincidentally placed the two in the same classes as the prettiest girls in school. Still in high school, Gates and Allen founded a company called Traf-O-Data, which analyzed city traffic data.

Gates set off for Harvard University intending to become a lawyer like his father. Still shy and awkward, he rarely ventured out to parties unless dragged by his friend Steve Ballmer, whom he later repaid by naming him president of Microsoft.

One day in December 1974, Allen, who was working at Honeywell outside of Boston, showed Gates a Popular Mechanics cover featuring the Altair 8800, a $397 computer from M.I.T.S. computing that any hobbyist could build. The only thing the computer lacked, besides a keyboard and monitor, was software. Gates and Allen contacted the head of M.I.T.S. and said they could provide a version of BASIC for the Altair.

After a successful demonstration at the company's Albuquerque headquarters, M.I.T.S. contracted with Gates and Allen for programming languages. The pair moved to New Mexico and started Micro-soft (they dropped the hypen later). Although the company's first five clients went bankrupt, the company struggled on, moving to Seattle in 1979. The following year, IBM asked Gates to provide an operating system for its first personal computer. Gates purchased a system called QDOS (Quick and Dirty Operating System) for $50,000 from another company, changed the name to MS-DOS, and licensed it to IBM. The IBM PC took the market by storm when it was introduced in 1981—and licensing fees streamed into Microsoft, ensuring the company's survival over the next several years.

Microsoft continued concentrating on the software market, adding consumer applications like Microsoft Word and Microsoft Excel. Through Gates' company Corbis, Microsoft acquired the vast Bettmann photo archives and other collections for use in electronic distribution. In 1986, when the company went public, Gates became a paper billionaire at the age of 31. The following year, the company introduced its first version of Windows, and by 1993 it was selling a million copies a month. When Windows 95 was introduced in August 1995, seven million copies were sold in the first six weeks alone. Microsoft's software became so ubiquitous that the U.S. Justice Department began a series of long-lasting antitrust investigations against the company, bogging it down in protracted legal battles.

In 1995, Gates dramatically changed the direction of the entire company