An actuator is something that converts energy into motion. It also can be used to apply a force. An actuator typically is a mechanical device that takes energy. usually, an energy that is created by air, electricity or liquid converts it into some kind of motion. That motion can be in virtually any form, such as blocking, clamping or ejecting. Actuators typically are used in manufacturing or industrial applications and might be used in devices such as motors, pumps, switches, and valves.