Formula One, abbreviated to F1 and also known as Grand Prix racing, is the highest class of single-seat open-wheel formula auto racing. It is a worldwide sport, involving an annual World Drivers Championship and World Constructors Championship, and is the most expensive sport in the world, as annual team budgets average in the hundreds of millions of US dollars. It is based around a series of races (19 in 2005), known as grands prix, on custom-constructed courses or closed-off street circuits.
