Gears can be manufactured by a variety of processes: casting, forging, extrusion, powder metallurgy, and blanking. But machining is applied to achieve the final dimensions, shape and surface finish in the gear. A gear/cogwheel – rotating machine part having cut teeth, or cogs, which mesh with another toothed part to transmit torque. It can change the speed, torque, and direction of a power source. The teeth on the two meshing gears all have the same shape so, the gears working in a sequence, are called a gear train or a transmission. More info about manufacturing process, in the video below!