Formula Ford (known as F1600 and Formula F in the United States because of a rule change in 2009) is an entry-level class of single seater, open-wheel formula racing. The various championships held across the world form an important step for many prospective Formula One drivers. Formula Ford has traditionally been regarded as the first major stepping stone into formula racing after karting. The series typically sees professional career minded drivers enter alongside amateurs and enthusiasts. Success in Formula F can lead directly to other junior formulae such as a Formula Renault 2.0 and Formula Three, or the W Series for female drivers.