Torx (pronounced "torks") developed in 1967 by Camcar Textron, is the trademark for a type of screw head characterized by a 6-point star-shaped pattern. People who are unfamiliar with the trademark generally use the term star, as in star screwdriver or star bits. The generic name is hexalobular internal driving feature (often abbreviated as 6lobe) and is standardized by the International Organization for Standardization as ISO 10664.Torx Plus is an improved profile.

By design, Torx head screws resist cam-out better than Phillips head or slot head screws. Where Phillips heads were designed to cause the driver to cam out, to prevent over-tightening, Torx heads were designed to prevent cam-out. The reason for this was the development of better torque-limiting automatic screwdrivers for use in factories. Rather than rely on the tool slipping out of the screw head when a torque level is reached, thereby risking damage to the driver tip, screw head and/or workpiece, the driver design achieves a desired torque consistently. The manufacturer claims this can increase tool bit life by ten times or more.