Celebrity·Posted on Dec 2, 2016How Well Do You Know These Britney Spears Songs?A journey through the pop singer's singles.by Whitney JeffersonBuzzFeed StaffLinkFacebookPinterestTwitterMail It's Britney Day, bitch. In honor of the legendary queen of pop's 35th birthday, BuzzFeed is celebrating with all things Britney Jean Spears. Check out more content on this legendary ICON here and buy Glory on iTunes!