Machinery parts are essential components of any machine, and they come in a variety of shapes and sizes. The three most common types of machinery parts are cams, cogs, and gears. A CAM is a rotating or sliding piece in a mechanical linkage used to transfer motion from one part of a machine to another. Cogs are toothed wheels that mesh with each other to transmit rotary motion. Gears are wheel-like objects with teeth around the circumference that mesh with other gears to transmit rotary motion. All three of these parts are essential for the proper functioning of any machine.