Motorboat

A motorboat generally speaking is a vessel other than a sailboat or personal watercraft, propel by an internal combustion engine driving a jet or a propeller. Though, the International Regulations for Preventing Collisions at Sea defines it as any vessel propelled by machinery. A speedboat is a small motorboat intended to move quickly, used in races, for pulling water skiers, as patrol boats, and as fast-moving armed attack vessels by the military. Even inflatable boats with a motor attached which may be serving as a high speed patrol boat or as a slow pedestrian dingy providing transport to and from a mooring buoy are technically classified as motorboats.
Here there are three popular variations of power plants: inboard, inboard/outboard, and outboard. If the engine is installed within the boat, it's called a power plant; if it's a detachable module attached to the boat, it's commonly known as an outboard motor.
An outboard motor is installed on the rear of a boat and contains the internal burning engine, the gear reduction (Transmission), and the propeller.