An electrode is defined as the small piece of metal or other substance that is used to take an electric current to or from a source of power, a piece of equipment, or a living body. An electrical conductor is a substance in which electrical charge carriers, usually electrons , move easily from atom to atom with the application of voltage. Copper, aluminium, silver, mercury, etc. are some of the examples of the conductor.The material through which electricity can pass easily, or it conducts electricity is called a good conductor of electricity. The material through which no electricity can pass is called Insulator or poor conductor. Example: wood, paper etc.