Copper and its alloys are widely used because of their outstanding conductivity, workability and resistance to corrosion. Selected alloys from the principal groups of copper-based materials are presented, including unalloyed coppers, high-copper alloys, brasses, and bronzes, highlighting the capability of this class of materials. The description of the alloys is presented with a strong focus on physical metallurgy, i. e., basic considerations of the phase equilibria in binary systems are drawn and linked to the mechanical and physical properties of the alloys. This chapter pinpoints the potential of the alloys based upon their properties and includes essential information important for materials selection.