Simplify the following text for a Grade 7 native English-speaking person.
Original: Open-wheel car , formula car , or often single-seater car in British English , describes cars with the wheels outside the car 's main body and , in most cases , one seat .
Simplified: Open-wheel car describes cars with the wheels outside the car 's main body and , in most cases , one seat . Other names include formula car , single-seater car in British English , or Indy car in the United States .