What's the difference between team pursuit, long-track, mass start, and short-track speed skating?
Traditional, long-track speed skating takes place on a 400 meter ice track, with skaters racing counter-clockwise around an oval for a set number of meters (between 500 meters and 10,000 meters). In individual races, pairs of skaters face off against one another on the track at a time, one person in each lane, competing to complete the designated distance in the fastest time of all competitors (not just the person they're matched up against at the moment).
Team pursuit speed skating events also takes place on a 400 meter course, but involves two teams of three racing against one another. Teams start on opposite sides of the oval, and in order to win, all three team members must all cross the finish line before all three skaters on the other team (simple enough, right?). These races are single elimination, meaning the only way to advance to the semifinals or finals is to beat whatever team you're up against.