They are how many "Flashbacks" you get. A Flashback is the games version of a do over, if you flub in the game, you can go back to the reply by pressing Select. rewind to before you messed up, and hit "X" (or Square on PS3". this will set you back to before you're crash. it was first in GRiD, and was put into DiRT 2 as well, it's a great system.