Escalators

An escalator is a moving staircase -a conveyor transport device for carrying people between floors at a building, The device consist of a motor-driven chain of individually ' linked steps that move up or down on tracks. allowing the step treads to remain horizontal. Escalators are used around the world to move pedestrian trallic in places where elevators would be impractical. Principal areas of usage include department stores, shopping malls,airports, transit systems, convention centers, hotels, arenas. stadiums, train stations (subways) and public buildings etc.