An actuator is a device that is used to effect a change in the environment such as the temperature controller of an air conditioner.
The three main types of actuators are pneumatic (air pressure), hydraulic (fluid pressure) and electric.
The most common kind of actuator is an electrical one which can take electrical energy from DC or AC and turn it into mechanical energy.
Because this is a clean and easily available technology, electrical actuators are popular for many types of industry and things like multi-turn valves.
An Internet of Things (IoT) gateway is a physical device or software program that serves as the connection point between the cloud and controllers, sensors and intelligent devices.
IoT Gateway manages the bidirectional data traffic between different networks and protocols.
Another function of gateway is to translate different network protocols and make sure interoperability of the connected devices and sensors.