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
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.