A pin is a device used for fastening objects or material together. Pins often have two components: a long body and sharp tip made of steel, or occasionally copper or brass, and a larger head often made of plastic. The sharpened body penetrates the material, while the larger head provides a driving surface. It is formed by drawing out a thin wire, sharpening the tip, and adding a head. Nails are related, but are typically larger. In machines and engineering, pins are commonly used as pivots, hinges, shafts, jigs, and fixtures to locate or hold parts.