What are the two general types of elevators?

Elevators are primarily categorized into two general types based on their mechanisms of movement: traction and hydraulic.

Traction elevators operate using a system of ropes and pulleys, where a motor drives the movement of the elevator car via a sheave that rotates and lifts or lowers the car. This system provides a smooth ride and is efficient for taller buildings, making it the preferred choice for high-rise structures.

Hydraulic elevators, on the other hand, use a hydraulic system to lift the elevator car. A pump pushes hydraulic fluid into a cylinder, which raises the car. This type is typically used for low-rise buildings due to its ability to provide a powerful lift but with limitations on the height it can effectively service.

Understanding these two types helps in comprehending their specific applications, advantages, and limitations, especially concerning building design and fire service operations.