This article provides information on the Unified Numbering System designations and temper designations of copper and copper alloys. It discusses the basic types of heat treating processes of copper and copper alloys, namely, homogenizing, annealing, and stress relieving, and hardening treatments such as precipitation hardening, spinodal hardening, order hardening, and quench hardening and tempering. The article presents tables that list the compositions and mechanical properties of copper alloys. It also discusses two strengthening mechanisms of copper alloys, solid-solution strengthening and work hardening. Finally, the article provides information on the equipment used for the heat treating of copper and copper alloys, including batch-type atmosphere furnaces, continuous atmosphere furnaces, and salt baths.