Page "Electrical conductor" Paragraph 1

In physics and electrical engineering, a conductor is a material which contains movable electric charges.

In metallic conductors such as copper or aluminum, the movable charged particles are electrons ( see electrical conduction ).

Positive charges may also be mobile, such as the cationic electrolyte ( s ) of a battery, or the mobile protons of the proton conductor of a fuel cell.

Insulators are non-conducting materials with few mobile charges and which support only insignificant electric currents.