Copper is a chemical element of symbol Cu atomic number 29 (29 protons and 29 electrons) and atomic mass 63.54 u. At room temperature the copper is in the solid state.

Classified as transition metal, it belongs to group 11 (1B) of the Periodic Classification of Elements. It is one of the most important metals industrially, of reddish colour, ductile, malleable and good conductor of electricity.

Known since prehistory, copper is currently used for the production of conductive materials of electricity (wires and cables), and in metal alloys such as brass and bronze.