Ambushing mid-'90s radio smack in the middle of grunge's extended hangover, this genre-defining Florida boy band made their name with a string of ultra-romantic blockbuster ballads, including “I Want It That Way” and “Quit Playing Games (With My Heart).” Between their perfectly calibrated harmonies, airtight dance choreography, and producer Max Martin's cutting-edge merger of pop and R&B, Backstreet Boys dominated the second half of the decade. The pure rush of jubilation bottled by “Everybody (Backstreet's Back)” sealed the deal, perfecting a template for successors like One Direction.