This year saw the return of the music video as an event, thanks to platforms like Vine, Instagram and, of course, YouTube. The last still reigned supreme as the place to visit for the visual accompaniment to the day's hit songs. There, clips from some of today's biggest artists – including Adele, Ellie Goulding and Fifth Harmony – brought in massive numbers as they raked in close to a billion views — and, for one, over a billion — in less than 12 months. Here are 10 of the most-watched music videos on YouTube.