A pulley system is a simple machine that consists of a wheel on an axle or shaft designed to support movement and change the direction of force. It typically uses a rope or cable that runs over the wheel, allowing heavy objects to be lifted with less effort. Pulleys can be used individually or combined in a block-and-tackle system to increase mechanical advantage. Pulleys are commonly found in various applications, such as cranes, elevators, and theater rigging. They help in lifting and lowering loads efficiently, making tasks easier and safer. Understanding how pulleys work is essential in fields like engineering and construction.