Self-tapping is the ability of a screw to advance when turned while creating its own thread. This ability is created sometimes by creating a gap in the continuity of the thread on the screw. These edges can cut their own threads as the screw is driven in to the material, usually wood or plastic. They function by having a cutting
edge which drills away the material, making a hole for the screw to go into.

Self-tapping screws are intended for small fixing applications into hard woods, soft woods, plywoods, composite boards, soft plastics, sheet metals etc. As the name suggests, self tappers create there own mating threads as they are applied, to give a vibration resistant assembly.

Self-tapping screws have a high tensile strength and are durable enough to handle repeated assembly and disassembly. There are two different kinds of self tapping screws: thread forming and thread cutting.