Today is the day you've been waiting for. Well, it's the day many of us here at PopEater HQ have been waiting for. After two smokin' singles, Britney Spears' 'Femme Fatale' has finally dropped, and the verdict seems to be that the pop bombshell has done it again.

Critics are loving Spears' latest set, with Rolling Stone giving it four stars and Entertainment Weekly saying in its B+ review, "The album is a ballad-free, treadmill-ready playlist of tireless dance beats and top-shelf production." In honor of Britney's big day, we thought we'd take a little time to introduce those less familiar with Kentwood, Louisiana's most famous export to some essential Spears. We're not talking singles, kids. When it comes to Brit, we're not exactly amateurs, so we dove deep into her catalog to bring you her five best non-single album tracks. Without further ado, here is PopEater's guide to the Five Best Britney Spears Songs You Probably Don't Know.