An electric gate is an entrance gate which can be opened and closed via an electric powered mechanism.
A sliding electric gate with electric motor and backup battery in case of mains failure. Note also the Infrared obstacle sensor located on the wall to prevent the gate from closing while a vehicle or other obstacle is in the way.
The motor of any electric sliding gate is much like any other door motor. There is a simple circuit that makes the gate work. Your vehicle is usually fitted with a transmitter that sends a radio signal to a receiver box mounted close to the gate. The receiver is in turn wired to a control box.