The racers are basically a seat hooked to two giant engines, propelling the rider to victory or death. Or sometimes second place. Or third place. And so on.
Humans and humanoids tend to be poor podracers due to their size. Most podracers come from ridiculous-looking, anatomically impossible species that can't be found anywhere else in the Galaxy.
Many feel that podracing is exciting and entertaining, while others think it is a waste of time and is just used as a distraction so nobody realizes that the story doesn't make any sense.