actuator

An actuator is a mechanism for turning energy into motion. 

Actuators can be categorized by the energy source they require to generate motion. For example:

• Pneumatic actuators use compressed air to generate motion.
• Hydrolic actuators use liquid to generate motion.
• Electric actuators use an external power source, such as a battery, to generate motion. 
• Thermal actuators use a heat source to generate motion. 

The data that is generated by sensors and actuators are expected to play an important part in the Internet of Things (IoT).