Screws and fasteners are components used to join multiple pieces of material, and the two terms are often used interchangeably. Screws are a type of fastener that are typically made from metal and feature a cylindrical shape with threads on the outside. This threading allows them to be inserted into a material, such as wood, metal, or plastic, and securely fastened. Commonly used fasteners in addition to screws are nuts, bolts, nails, and rivets. These fasteners require some kind of tool to insert and secure, such as a screwdriver, hammer, or wrench.