Escalator

An escalator is a moving staircase which carries people between floors of a building or structure. It consists of a motor-driven chain of individually linked steps on a track which cycle on a pair of tracks which keep them horizontal.Escalators are mechanical devices used for transporting people vertically between different levels of buildings. Typically, they take the form of a moving staircase, consisting of a 'chain' of single-piece aluminium or stainless steel steps guided by a system of tracks in a continuous loop.