Formula One, abbreviated to F1, is the highest class of open-wheeled auto racing series managed by the Fédération Internationale de l'Automobile (FIA), motorsport's world governing body. The "formula" in the name alludes to a series of FIA rules to which all participants and vehicles are required to conform. The Formula One World Championship season consists of a series of races around the world, known as Grands Prix, usually held on purpose-built circuits, and in a few cases on closed city streets. Each Grand Prix meeting lasts three days with either one or three practice sessions before a three-part qualifying session on Saturday to set the starting order for Sunday's race. A Saturday sprint is held at select events, with the starting grid determined by a separate, shorter qualifying session held on Friday. Grands Prix are frequently named after the country, region or city in which they are raced, and in some seasons, nations have hosted more than one event. Should Formula One hold two or more races in the same nation in the same year, on either a different or the same track, then their names will be different. The results of each Grand Prix held throughout the season are combined to decide two annual championships, one for drivers and one for constructors.
Grand Prix distance regulations have varied throughout Formula One history. Between 1950 and 1957, events ran for more than 300 km (190 mi) or three hours. In 1958, race lengths were set between 300 and 500 km (190 and 310 mi) or two hours. It was reduced to between 300 and 400 km (190 and 250 mi) from 1966 with an established maximum length of 321.87 km (200.00 mi) in 1971. From 1973 to 1980, races had to last either 321.87 km (200.00 mi) or two hours, whichever came first. Distances of between 250 and 320 km (160 and 200 mi) or two hours were used from 1981 to 1984. The minimum distance was revised to 300 km (190 mi) including the formation lap in 1984 and the maximum length was standardised at 305 km (190 mi) in 1989. The exception to the rule is the Monaco Grand Prix, which has a scheduled length of at least 260 km (160 mi). No race can last more than two hours if it goes unhalted. From 2012, the maximum permitted race time including probable stoppages was four hours, before being reduced to three hours for 2021.
