Escalator

An escalator is a conveyor transport device for transporting people, consisting of a staircase whose steps move up or down on tracks that keep the surfaces of the individual ladder horizontal. As a power-driven, continuous moving stairway planned to transport passengers up and down short vertical distances, escalators are used around the world to move pedestrian traffic in places where elevators would be impractical. Principal areas of usage include shopping centers, airports, transit systems, convention centers, hotels, and public buildings.

They have the capacity to move large numbers of people, and they can be placed in the same physical space as set of steps. They have no waiting interval, except during very heavy traffic, they can be used to guide people towards main exits and they may be weather-proofed for outdoor use.