Since its inception in 1999, Coachella has been one of the biggest festivals in the world, and the one that sets the stage for the rest of the summer. This year, Radiohead, Lady Gaga and Kendrick Lamar will headline the festival. They'll be accompanied by some other heavy hitters, such as Gucci Mane, Mac DeMarco, BANKS, Lorde, Justice, Devendra Banhart and lots more.