Oprah Winfrey is an American media executive, television host, actress, and philanthropist. She rose to prominence with 'The Oprah Winfrey Show,' which ran for 25 years and became one of the most influential talk shows in history. Winfrey has built a multimedia empire, including her production company Harpo Productions, and is known for her charitable work, advocacy for education, and cultural impact. She is widely regarded as one of the most powerful women in media.