Fifteen years ago, did you imagine that we would still be talking about the school girl with pigtail braids? Britney Spears was 17 when she released '...Baby One More Time' in 1998 She received a Grammy nomination for the hit, and helped redefine the sound of pop music.

"Because of that sound and because of songs like it, we had this sort of rush of pop music again on the charts, and on the radio where we hadn't really had that in a while," says Keith Caulfield, Associate Director of Charts for Billboard to ABC radio. " Britney was kind of, you know, at the forefront of that parade of pop."

Britney topped the charts with the help of Swedish Pop mastermind, Max Martin, who had already had success with the Backstreet Boys and later with many others. In fact, Martin helped create the #1 song in the country today, Katy Perry's 'Dark Horse.'

"Max Martin has gone on to produce and co-write more than a dozen number-one singles on the Billboard Hot 100 chart," explains Caulfield. "[He's] sort of the architect of so many pop hits that we've known and loved for the past 15 years, but that was sort of where it all started."

Britney's video also helped to create buzz. Watch as she croons the provocative chorus and struts in her school girl uniform. All at once the envy of girls and the dream of boys everywhere.