A stock car is a type of automobile that is specifically designed for racing. These cars are built to resemble standard production vehicles but are modified for performance and safety. They typically feature powerful engines, reinforced frames, and specialized tires to handle high speeds on racetracks. In professional racing, such as in the NASCAR series, stock cars compete on oval tracks and road courses. The term "stock" refers to the car's origins from mass-produced vehicles, although the racing versions are significantly altered to enhance speed and handling.