Determining which car is the fastest in the world can get complicated quickly. Here are why various cars claim they are the fastest.

The Czinger 21C, an American hybrid hypercar built using groundbreaking 3D-printing technology, set a new record for the fastest road-legal production car to ever sprint up the Goodwood hill.

In fact, during a recent track test of the car it hit a GPS-indicated 215 miles per hour, making it the fastest four-door in the history of the automobile.