Heat treating is a common term used in the manufacturing industry to describe a process in which metal materials are treated with heat in order to manipulate their physical properties. There are several other terms that are often used interchangeably with heat treating, including annealing, tempering, and quenching. Annealing is a process that involves heating and cooling metal materials to increase their ductility and reduce internal stress. Tempering involves reheating and cooling materials to improve their strength and hardness. Quenching refers to rapidly cooling materials to transform their atomic structure and create a harder surface. These terms are all related to the general process of heat treating, but each has its own specific application and outcome.