AGE 25: Taylor Swift

Musician

What makes her powerful: Swift's latest album, "1989," which was the best-selling album of 2014, made her the first woman to have three albums sell more than a million copies in a single week. With a net worth around $200 million, Swift is powerful in more than just the music industry; retail brands like Victoria's Secret use her to boost sales. Fans love her as she interacts with them directly and demonstrates a new way of keeping it real as a celebrity.