Dirt track racing is a type of
auto racing performed on clay or dirt surfaced
oval tracks. It began in the United States before World War I and became widespread during the 1920s and 30s. Two different types of race cars dominated—
open wheel racers in the Northeast and West and
stock cars in the South. While open wheel race cars are purpose-built racing vehicles, stock cars (also known as fendered cars) can be either purpose-built race cars or street vehicles that have been modified to varying degrees.