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A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The load is attached to the hoist by means of a lifting hook.
A "hoist" normally is used for lifting (near vertical) and a winch is normally used for pulling (near horizontal).
Construction sites, especially for buildings of more than five floors in height, often employ hoists to lift workers and building materials.
Types of Hoist
The basic hoist has two important characteristics to define it: Lifting medium and power type. The lifting medium is either wire rope, wrapped around a drum, or load-chain, raised by a gear-like wheel. The power type can be either electric motor or air motor. Both the wire rope hoist and chain hoist have been in common use since the 1800's.