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 alludes to a series of rules established by the FIA to which all participants and vehicles are required to conform. Each year, the F1 World Championship season is held, consisting of a series of races, known as , held usually on purpose-built circuits, and in a few cases on closed city streets. Constructors are awarded points based on the finishing position of each of their two drivers at each Grand Prix, and the constructor who accumulates the most points over each championship is crowned that year's World Constructors' Champion. As of the 2021 Belgian Grand Prix, there have been 171 Formula One constructors from 24 different national racing licences who have raced at least one of the 1,047 FIA World Championship races since the first such event, the 1950 British Grand Prix.