A threaded fastener is a device used to hold two or more objects together. It is composed of a head, a shank, and a thread. The most common types of threaded fasteners are screws, woodscrews, nuts, tnuts, and bolts. A SCREW is a type of fastener with a helical ridge, or thread, that is used to secure two objects together. A woodscrew is a type of SCREW specifically designed for use in wood. A NUT is a type of fastener with an internal thread that is used in conjunction with a BOLT or SCREW. A tnut is a type of NUT with a threaded barrel that is inserted into a pre-drilled hole. Finally, a BOLT is a type of fastener with an external thread that is used in conjunction with a NUT.