To aspiring celebrities, she is a springboard to stardom; to Middle America, she is nothing short of a lifestyle guru. She even gave Obama a nudge through the door of the White House.
Besides this, she has become a symbol of wider cultural achievement, whether as the rags-to-riches story of the American dream, one of the world's few black billionaires, or the most influential woman on the planet.
As she retires from her talk show after 25 years, there are rumours of senatorial ambitions. Oprah will not be out of the limelight for long.
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