2. Bill Gates

Benjamin Wachenje

Founder, Microsoft; co-chair, Bill & Melinda Gates Foundation
Born: Oct. 28, 1955, Seattle
Education: Harvard University (dropped out)

William Henry Gates III had an idea back when computers were still mainframes or the domain of Popular Electronics hobbyists: One day a personal computer would be on every office desk and in every home, and he could make a royalty from each one running his software under license. That idea led to what became the world's largest PC software company, which Gates created with Paul Allen, a friend from Lakeside, the Seattle prep school the two had attended. Their company, Microsoft, shaped the user experience for the first era of the PC revolution, which transformed daily life for billions of businesses and individuals worldwide.

A rare acumen for software development and technological innovation, as well as forceful business tactics, helped make Gates a billionaire by 31. His MS-DOS and Windows operating systems, and productivity software such as Microsoft Word and Excel, let Microsoft dominate the early-Internet phase of desktop computing. Gates was the world's richest person in every year but one between 1995 and 2009. He is again, according to Forbes, which figures his worth at $76 billion.

Gates' 4.3 percent stake in Microsoft accounts for one-fifth of his wealth. Most of the rest comes from his Cascade Investment, a vehicle originally funded with $31 billion of his sale of Microsoft stock as he diversified his holdings. Gates has donated $28 billion to the global foundation he started with his wife, Melinda, in 2000, the year he stepped down as Microsoft's CEO and created a new position for himself as chief software architect.

Microsoft had started 25 years earlier, when Gates dropped out of Harvard and joined Allen in Albuquerque, N.M., to develop a BASIC interpreter—which allows users to write programs in a higher-level language—for the first microcomputer, Micro Instrumentation and Telemetry Systems' Altair 8800. Gates and Allen parted ways with MITS in 1979, moving back to Washington to continue work on Microsoft BASIC.

IBM came calling in 1980, looking for a BASIC compiler and an operating system for its forthcoming personal computer—the hardware piece that would enable Gates' software vision. Lacking an operating system of his own, Gates licensed 86-DOS from Tim Paterson of Seattle Computer Products for $50,000, without mentioning IBM's interest. He then re-licensed it at cost to Big Blue, which marketed it as PC-DOS. Gates' smartest move was retaining ownership of the source code of what he and Allen would develop as MS-DOS. Microsoft got a licensing fee every time IBM sold a PC and was free to license its software to the PC-clone manufacturers that Gates correctly guessed would quickly spring up.

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As the PC business exploded, Gates broadened Microsoft's product range. Windows, an Apple-like graphical extension for MS-DOS, appeared in 1985. Five years later, the word processing program and spreadsheet were bundled into Microsoft Office, and a slide-based presentation program, Microsoft PowerPoint, was added. Both Windows and Office became dominant in their areas.

Gates' reputation as a ruthless competitor grew within the industry, just as his confrontational management style became legend inside Microsoft. His vigorous defense of the company's market positions and its business practices led to antitrust litigation by several governments and rivals in the 1990s. Microsoft was accused of making unfair deals with computer makers that installed the Windows operating system on their computers and forcing manufacturers to include its Internet Explorer browser as a condition for selling the Windows OS with their computers.

Following his 1995 internal memo predicting that communications networks would replace computing power as the industry driver, Gates refocused Microsoft on the Internet. He wanted to secure Windows as the main platform for companies and consumers to use the Web, and to create applications and content for it, noting that the most important aspect of the Internet "is that it has bootstrapped itself as a place to publish content."

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Microsoft created operating systems for personal digital assistants and mobile phones, and got active in areas including Internet search (with Bing), video gaming (with the Xbox) and digital services (through MSN). With NBCUniversal (CNBC's parent), it created a 24/7 cable news station, MSNBC. In its largest acquisition, Microsoft bought Skype Technologies, an Internet telephony company, for $8.5 billion in October 2011.The following year it entered the hardware market with Microsoft Surface tablet computers.

But none of these moves could equal the preeminence of MS-DOS and Office, and the aging software giant struggled with the resurgence of its archrival Apple and the arrival of Internet companies such as Google. Microsoft's share price has never regained its 1999 peak.

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In 2000, Gates and his wife combined three family foundations to establish the Bill & Melinda Gates Foundation, with the goal of addressing problems in public health and education that governments and nongovernmental organizations can't or won't take on. It is now the world's wealthiest charitable foundation.

Gates retired from day-to-day involvement as Microsoft's chief software architect in 2008 to devote his energies to his foundation. With the retirement this year of Steve Ballmer, his Harvard friend and successor as CEO, Gates stepped down as chairman to become more active again within the company as technology advisor.

Bill Gates: Lifelong highlights

• Served as a congressional page in the U.S. House of Representatives in 1972
• Created three billionaires and about 12,000 millionaires among employees when Microsoft went public in 1986
• Paid the Rolling Stones $10 million for the rights to use "Start Me Up" in a Microsoft ad
• Bought the Bettmann Archive of 19 million photographs in 1995 as the core for his digital media company Corbis Images
• Reads avidly and has published two best-sellers of his own, "The Road Ahead" and "Business @ the Speed of Thought"

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