Formula racing
Formula racing is a set of classes of motor vehicles, with their wheels outside, and not contained by, any bodywork of their vehicle. These have been globally classified as specific 'Formula' series - the most common being Formula One, and Formula Two. Many others include the likes of Formula 3, Formula Ford, Formula Renault and Formula Palmer Audi. However, in North America, the IndyCar series is the most followed open-wheeled racing series. Former 'Formula' series include Formula 5000, GP2 and GP3.