18. Meg Whitman

President and CEO, Hewlett-Packard
Born: Cold Spring Harbor, N.Y., Aug. 4, 1956
Education: Bachelor's in economics, Princeton University; MBA, Harvard Business School

Meg Whitman is the only woman to have headed two large U.S. public companies: eBay and Hewlett-Packard. Until Marissa Mayer's arrival at Yahoo, she was the only female head of a leading Internet-based company. The firms, eBay and HP were two storied West Coast companies at different points in their histories when she took over, but both were managerial messes.

She became CEO of the online auction and shopping site in March 1998. Pierre Omidyar's 3-year-old start-up had 30 employees, annual revenue of less than $5 million and erratic growth. After 10 years at the helm, she left it dominating its market with $8 billion in sales,15,000 employees and operations in 30 countries. Whitman raised eBay's market valuation from $7.7 billion in 1998 to a high of $57 billion in 2004, establishing her as a role model for both men and women as one of the most effective chief executives in the U.S.

Forthright, hands-on and persistent, Whitman led eBay through its initial public offering six months after joining the company. She also steered it through the collapse of the dot-com bubble in 2000-01. She expanded the business internationally, and acquired the online payments system PayPal in 2002 for $1.5 billion and Internet telephony company Skype in 2007 for $2.75 billion. (Microsoft bought it in 2011 for $8.5 billion.)

25 years later: The dramatic change in gadgets

By then the fourth-wealthiest woman in California, with a fortune estimated by Forbes at $1.3 billion, Whitman stepped down from eBay to pursue a political career.

She co-chaired Republican Sen. John McCain's presidential campaign in 2008. In 2010 she ran to succeed Arnold Schwarzenegger as California's governor. After spending $144 million of her own money on the race, she lost to her Democratic opponent, former Gov. Jerry Brown.

The last 25 years: What's changed, who mattered...

Shortly after the defeat, Whitman joined Hewlett-Packard's board. She took over as CEO in September 2011 after HP fired Léo Apotheker. It had lost $30 billion in market capitalization—more than a third of its value—during his tenure of less than a year. She reversed Apotheker's decision to sell the PC business and, as she had at eBay, reorganized HP's businesses in product clusters.

Whitman still bears the burden of years of misguided software acquisitions at HP. Two and a half years into cleaning up the strategic shambles she found at Silicon Valley's original garage start-up, the tech CEO still has a way to go to cap her legacy by leading a turnaround to match Lou Gerstner's at IBM.

Meg Whitman: Lifelong highlights

• Started career as brand manager for Procter & Gamble; now sits on board
• Relaunched Mr. Potato Head for Hasbro
• Gained reputation at eBay as a swift decision maker and a charismatic communicator
• Donated $30 million to Princeton for Whitman College

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