Below is the definition of gate and gate operator extracted from Wikipedia.
“A gate or gateway is a point of entry to a space enclosed by walls, or a moderately sized opening in some sort of fence. Gates may prevent or control the entry or exit of individuals, or they may be merely decorative. Other terms for gate include yett and port. The word derives from the old Norse "gata", meaning road or path, and originally referred to the gap in the wall or fence, rather than the barrier which closed it.
A gate may have a latch to keep it from swinging and a lock for security. Larger gates can be used for a whole building, such as a castle or fortified town, or the actual doors that block entry through the gatehouse. Today, many gate doors are opened by an automated gate operator.”
“A gate operator is a mechanical device used to open and close a gate, such as one at the end of a driveway. There are two main types of electric gate openers – hydraulic or electromechanical; these can be further split into the following categories, worm (or screw) driven, arm openers and underground openers. Automatic and Electric Gate operators are designed for both swinging and sliding gates. They can be programmed to open and close with a wireless transmitter or a manual device. Low Voltage Automatic Gate openers can also be fitted with solar panels to ensure function during loss of electricity or blackouts.”