A sprocket[1] or sprocket-wheel[2] is a profiled wheel with the teeth, or cogs,[3][4] that mesh with a chain, monitor or other perforated or indented materials.[5][6] The name ‘sprocket’ applies generally to any wheel upon which radial projections engage a chain passing over it. It really is distinguished from a equipment in that sprockets should never be meshed together straight, and differs from a pulley in that sprockets have teeth and pulleys are even.
Sprockets are found in bicycles, motorcycles, vehicles, tracked automobiles, and other machinery either to transmit rotary motion between two shafts where gears are unsuitable or even to impart linear motion to a track, tape etc. Maybe the most typical form of sprocket may be found in the bicycle, where the pedal shaft bears a huge sprockets sprocket-wheel, which drives a chain, which, in turn, drives a little sprocket on the axle of the rear wheel. Early automobiles were also largely powered by sprocket and chain system, a practice mainly copied from bicycles.
Sprockets are of varied designs, no more than efficiency becoming claimed for every by the originator. Sprockets typically don’t have a flange. Some sprockets used with timing belts have flanges to keep the timing belt centered. Sprockets and chains are also utilized for power transmission from one shaft to another where slippage isn’t admissible, sprocket chains being 
used rather than belts or ropes and sprocket-wheels instead of pulleys. They could be operate at high speed plus some types of chain are so constructed concerning be noiseless also at high speed.