Electrode

Electrode, electric conductor, usually metal, serves as either of the two terminals of an electrically conducting medium. It conducts current into and out of the medium, which may be an electrolytic solution as in a storage battery, or a solid, gas, or vacuum. The electrode from which electrons emerge is called the cathode and is designated as negative; the electrode that receives electrons is called the anode and is designated as positive. There are various types of electrodes, such as cathodes, anodes, welding electrodes, electric furnace electrodes, etc.