An elevator is a button-controlled popular form of commercial building transportation that moves people and products from floor to floor. For example, in a 12-story building the elevator is designed to stop at each floor. Attached to one end of a steel cable, an elevator is like a steel cage, with cables moving up and over a sheave (a grooved drive wheel) and downward toward a counterweight of iron blocks. The elevator is powered by an electric motor which moves the car as well as the counterweight between the enclosed staff and steel guide rails.
Escalators, another form of commercial transportation, consist of a chain of moving steps that transport large number of people between floors. The step treads remain horizontal while moving people. Like elevators, escalators are used all over the world. However, escalators transport pedestrian traffic to places where elevators are impractical. Shopping malls, department stores and hotels as well as public buildings use escalators.
Moving walkways, usually found in airports, are designed to move people over long distances, usually between different terminals. Moving walkways are similar to an escalator. The only difference is that the steps lay flat, like a conveyor belt. Passengers are able to move from gate to gate or from one baggage area to the next. Moving walkways, like elevators and escalators, offer a smooth and convenient ride for people while providing outstanding energy efficiency for commercial building operators.
When riding commercial transportation, people must abide by safety rules and regulators to avoid injury. Overloading elevators or running up escalators can result in serious harm or worse. Although some commercial building transportation may allow a person to walk while the transportation is in operation (such as moving walkways) running is mostly forbidden everywhere.
