7. Oprah Winfrey

Benjamin Wachenje

Chairwoman and CEO, Oprah Winfrey Network
Born: Jan. 29, 1954, Kosciusko, Miss.
Education: Bachelor's degree in communications, Tennessee State University

One of a small group of celebrities known by one name, Oprah is a member of an even more elite group: self-made female billionaires. And she is sui generis as the first black American female billionaire and the richest black American. With a fortune estimated by Forbes at $2.9 billion, she has also passed Hewlett-Packard CEO Meg Whitman as the richest self-made woman in the U.S.

But Oprah's mark on the past quarter-century goes beyond her classic rags-to-riches story. It lies in redefining the TV talk show, breaking the format's dominance by white men and building a personality-based brand on a scale never seen before. Those accomplishments have changed not just the media industry but American popular culture.

As a talk show host, Oprah's wit, warmth and well-grounded personality let her pioneer and popularize confessional tabloid talk TV. Her ability to get celebrities and average people alike to pour out their emotions and confess all manner of indiscretions to an audience of strangers gave rise to the term Oprahization.

That phenomenon made a powerful ally to The Oprah Effect, or the power of her opinions and endorsements to sway public behavior—from buying titles highlighted in Oprah's Book Club to voting for Barack Obama for president, whom she endorsed in 2008 and 2012. Her success and popularity led to her repeatedly being named one of the most influential women in the world.

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

Oprah was born to a teenage single mother in Kosciusko, Miss. She grew up in inner-city Milwaukee, in well-documented hardship and abuse, and later was sent to live in Tennessee. She landed a part-time news job in local radio while in high school, and worked as a TV newscaster in Nashville and Baltimore before finding her true calling: the talk show.

In 1983, she moved to Chicago and a year later lifted the third-rated morning TV talk show there to No. 1, ousting "The Phil Donahue Show" from that position in the city. Within two years and still in her 30s, she launched her production company, Harpo (Oprah reversed), to create "The Oprah Winfrey Show" for national syndication. Debuting in 1986, it soon eclipsed "Donahue" as the highest-rated daytime talk show in the U.S., gaining a peak daily audience of 13.1 million in the 1991-92 season.

Look beyond Silicon Valley for lasting innovation

In the mid-1990s, Oprah transformed the program from a tabloid confessional centered on family and relationship issues to a show focusing on self-improvement. Her final episode aired in May 2011, four months after the launch of the Oprah Winfrey Network (OWN), a cable TV partnership with Discovery Communications, which has struggled.

Harpo Entertainment Group expanded the territory of the "Queen of All Media" to Hollywood and Broadway (as an actor and producer); books (Oprah has written five, with her 2005 tome on weight loss reportedly garnering the highest advance fee ever) and magazines (the upscale lifestyle title O); the airwaves (Oprah Radio); and public speaking (an eight-city tour has been announced for this fall). Harpo has also produced a next generation of popular talk shows, including those featuring Dr. Phil, Dr. Oz and Rachael Ray.

Oprah Winfrey: Lifelong highlights

• Named after the Biblical character Orpah, but a mispronunciation stuck
• Became the third woman in the U.S. entertainment industry—after Mary Pickford and Lucille Ball—to own her own studio
• Awarded the U.S. Presidential Medal of Freedom in 2013

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