Sprockets are sturdy wheels with teeth that lock onto a chain. As the sprocket spins, the teeth grab onto the chain and move other parts that interlock with the chain. This sequential series of operations allows for simple and controlled rotational movement of larger equipment and machinery.

Sprockets are often made from metal or reinforced plastics that can withstand the force of moving the chain. These components are often compared to gears, which share a similar wheel-shaped design with teeth. Unlike gears—which interlock together to transfer rotational movement— sprockets only directly interact with different types of chains. Rather than a gear system, most sprocket and chain systems work in a similar manner to bicycle chain assemblies—which is itself a lightweight sprocket and chain assembly.