Formula One, abbreviated to F1, is the highest class of open-wheeled auto racing defined by the Fédération Internationale de l'Automobile (FIA), motorsport's world governing body. The "formula" in the name refers to a set of rules to which all participants and cars must conform. The F1 World Championship season consists of a series of races, known as Grands Prix, held usually on purpose-built circuits, and in a few cases on closed city streets. The polesitter is the driver that has qualified for a Grand Prix in pole position, at the front of the starting grid. Out of the 1,161 completed Grands Prix, the driver that has started in first has gone on to win the race 506 times.