Automatic Elevator

elevator, also called lift, car that moves in a vertical shaft to carry passengers or freight between the levels of a multistory building. Most modern elevators are propelled by electric motors, with the aid of a counterweight, through a system of cables and sheaves (pulleys).Elevator doors have two major types, manual and automatic. Manual doors are normally opened and closed manually by hand, and automatic doors are the standard type of doors found in modern days elevators, usually powered by a door operator.