A pulley, which is a basic machine, usually has a rope and a wheel. One end of the rope is tied to the load, while the other end is fitted into the wheel. When the pulley is pulled on one side, the wheel turns, which will move the load. A pulley makes it easy for moving loads sideways, up or down.
A pulley is considered a type of lever, and the pulley's center acts as the fulcrum. The load is at one end, and the effort is at the other end. A block and tackle is a system that has more than one pulley.Learn more about Motion & Mechanics