A belt system is a mechanical device used to transfer power between rotating shafts in machines. It consists of a continuous loop of flexible material (the belt) that connects pulleys or gears on the shafts. As one pulley rotates, the belt transfers the rotational motion to the other pulley, enabling the transmission of mechanical power across varying distances. Belt systems are commonly found in engines, conveyors, and industrial machinery, offering a simple, efficient means of power transmission with minimal slippage. Types include V-belts, flat belts, and timing belts.