A moped (/ˈmoʊpɛd/ MOH-ped) is a small motorcycle, generally having a less stringent licensing requirement than motorcycles, or automobiles, because mopeds typically travel about the same speed as bicycles on public roadways. Strictly speaking, mopeds are driven by both an engine and by bicycle pedals, but in common usage and in many jurisdictions the term moped is used for similar vehicles including a scooter. Mopeds occasionally resemble powered bicycles, more commonly called a motorized bicycle. Some mopeds are of a step-through type design, while others are step-over designs, having a motorcycle-like frame, including a "backbone" and a raised fuel tank, mounted directly between the saddle, and the head tube. Most are similar to a regular motorcycle, only having the addition of pedals, in which the rider can both manually power the vehicle through a bicycle-like crankset in addition to a small displacement engine. Although mopeds usually have two wheels, some regions classify low-powered three- or (rarely) four-wheeled vehicles as a moped.