Most-watched YouTube videos of all-time
Though silly pet videos might be the first thing that comes to mind when most people think of YouTube, the most-viewed uploads since the service launched in 2005 don't feature a single pet. In fact, of the estimated 72 hours worth of video uploaded every minute to YouTube, the most-viewed content is almost entirely music videos. But don't equate it with MTV just yet: one of the top all-time videos is not musical. Click through the gallery to find out which one.
All figures are current as of May 14, 2012.