Britney Spears' career began with a jolt. Dressed as a provocative school girl in pigtails and a plaid skirt, she became a mainstream obsession with 1999's ...Baby One More Time album and its chart-topping hits. The following year's Oops!... I Did It Again continued to reap the rewards of a bubblegum pop formula, before she hooked up with the futuristic sounds of The Neptunes production unit to take 2001's Britney in a fresh direction. Her status as a pop culture icon was confirmed when she teamed up with Madonna for a 2003 collaboration.