A multi-cylinder engine is an engine with two or more cylinders. It consists of several identical single-cylinders arranged on a single body to share a crankshaft output power. It is called a multi-cylinder engine. For example, two-cylinder, three-cylinder, four-cylinder, five-cylinder, six-cylinder, eight-cylinder, and twelve-cylinder are all multi-cylinder engines. Modern vehicle engines use four-cylinder, six-cylinder and eight-cylinder engines. The more the number of cylinders of the engine, the more uniform the crankshaft rotation and the smaller the vibration, but the manufacturing cost increases. The cylinders of a multi-cylinder engine are arranged in an in-line, V-shaped, and horizontally opposed manner depending on factors such as installation, manufacturing cost, and cooling method.