Taylor Swift

When the world first met Taylor Swift, she had long, blonde ringlets; her most defining physical feature ... but not anymore. These days, Swift keeps her hair super straight with a bold, blunt bang.

Does she pull it off? "Her bangs give her a sense of maturity and really helped change her overall look. Without the bangs, Taylor looks younger and more girlish," says Knudsen. As a young woman, it makes sense that Swift wouldn't want to hold onto her sweeter-than-honey teenage look. And it seems like her new style gave her a sophisticated edge; Swift's already appeared on the cover of "Vogue," "Glamour," and "Harper's Bazaar" in this past year alone.