An electrode is a terminal, usually in the form of a wire, rod or plate, through which electric current passes between metallic and nonmetallic parts of an Electric circuit.

The electrode through which current passes from the metallic to the nonmetallic conductor is called the anode; that through which current passes from the nonmetallic to the metallic conductor is called the cathode.

An electrode may be made of a metal e.g., copper, lead, platinum, silver or zinc or of a nonmetal, commonly carbon.