Who really knows why a video goes viral. But thousands of them have and the themes differ dramatically, from baby’s biting fingers to extraordinary singing to the evolution of dance. Thanks to Al Jazeera America, we’re treated to a condensed timeline of viral videos. And of course the timeline begins with our beloved Back Dorm Boys back in 2005, belting out Backstreet Boys’ I want it that way. This list goes through the years catching the good (Charlie bit my finger) to the very annoying yet unescapable (Gangnam style).