A motorcycle (also called a motorbike, bike, or cycle) is a single-track, engine-powered, two-wheeled motor vehicle. Motorcycles vary considerably depending on the task for which they are designed, such as long distance travel, navigating congested urban traffic, cruising, sport and racing, or off-road conditions. Motorcycles are one of the most affordable forms of motorised transport in many parts of the world and, for most of the world's population, they are also the most common type of motor vehicle.