Pulleys and idlers are essential components in various mechanical systems. Pulleys are grooved wheels used with ropes, belts, or chains to change the direction of force, lift loads, or transfer power efficiently, commonly found in cranes, conveyor systems, and industrial machinery. In contrast, idler pulley are passive wheels designed to guide belts or chains, maintain tension, and reduce vibration, ensuring smooth operation in systems like engine belt drives or conveyor belts. Together, pulleys and idlers form a vital combination for effective power transmission and system stability.