An automatic door is a door that opens sensing the approach of a person.
An electric gate is an entrance gate which can be opened and closed via an electric powered mechanism.
A swing-door operator (or swing-door opener or automatic swing-door operator) is a device that operates a swing door for pedestrian use. It opens or helps open the door automatically, waits, then closes it.
Convenience
Ease of use and Maintenance
Cost-Benefit Relationship
Energy Savings
Safety