elevator

An elevator, or lift, is a vertically mobile transport device that moves between floors to carry passengers or goods. It consists of a car suspended in a hoistway and guided by rails. Doors at each floor provide access to the car, and a control system coordinates movement and stopping.

Historical lifts ranged from simple rope-and-pulley hoists used in ancient times to modern electric systems. In 1853, Elisha Otis demonstrated a safety brake that made passenger elevators feasible for tall buildings, leading to rapid adoption in the late 19th and early 20th centuries.

Most contemporary elevators are powered by electric motors. Traction elevators use a counterweight and steel ropes that pass over a pulley; hydraulic elevators rely on a piston driven by fluid under pressure, suitable for low-rise installations. Machine-room-less designs place machinery within the hoistway. Pneumatic vacuum elevators operate in a sealed tube using air pressure, for very short routes.

Key components include the car, hoistway, counterweight, drive machine or pump, guide rails, doors, and safety devices such as interlocks and braking systems. Safety features also include overspeed governors, emergency communications, and regular maintenance and inspections. Elevators are governed by local and international codes to ensure reliability and rider safety. Modern systems emphasize accessibility and energy efficiency, with features like wide doors, low floor entries, tactile indicators, and regenerative drives that recover energy during operation.

Elevators enable high-density urban development by providing vertical mobility and reducing travel time between floors.