Microcar is a term often used for the smallest size of cars, with three or four wheels and often an engine smaller than 700 cc (43 cu in). Specific types of microcars include bubble cars, cycle cars, invacar, quadricycles and voiturettes. Microcars are often covered by separate regulations to normal cars, having relaxed requirements for registration and licensing.

A cyclecar was a type of small, lightweight and inexpensive motorized car manufactured in Europe and the United States between 1910 and the early 1920s. The purpose of cyclecars was to fill a gap in the market between the motorcycle and the car. A key characteristic was that it could accommodate only two passengers sitting in tandem.