Elevator
Skyscrapers are vital to the economies of large cities with limited area for buildings. Stacking one floor on top of another produces a lot of floor space for offices. However, skyscrapers would be impractical without elevators. Elevators allow people to be transported hundreds of feet in the air. The cable elevator is the most popular type today. Interpreting Diagrams What is the purpose of the counterweight?
Elevator motor
The elevator motor is needed to accelerate the car and compensate for the varying load.