A motorcycle sidecar is a single-wheeled device that is attached to the side of a motorcycle, moped/scooter, or electric or normal bicycle. The attachment of a motorcycle sidecar to a two-wheeler converts it into a three-wheeled vehicle. A two-wheeler with an attached motorcycle is also known as a combination, rig, or hack. The body of the motorcycle usually provides a seat for a single passenger, and has a small trunk-like compartment on the rear side of the body. In some cases, the motorcycle sidecar is modified for the transportation of cargo or tools & equipment, just like the platform of transport vehicles such as trucks.