In Pixar's Cars, Doc Hudson is the black 1951 Hudson Hornet known as the Fabulous Hudson Hornet.
Doc's model is based on the first-generation Hudson Hornet, an American car produced from 1951 to 1954. The real Hudson Hornet became famous in stock-car racing, especially through drivers such as Herb Thomas, whose success helped create the “Fabulous Hudson Hornet” nickname.
The film adapts that racing history into Doc's fictional biography. In the Cars world, he wins three Piston Cups before a crash and an unsympathetic racing establishment end his top-level career. He later settles in Radiator Springs and becomes the town's judge and doctor.
Doc's identity is revealed gradually, so the film initially presents him as a retired local rather than a legendary champion. He is distinct from The King, a Plymouth Superbird-inspired racer, and Sheriff, a black-and-white police car who patrols Radiator Springs.