The dipole moments in an antiferroelectric are arranged with an equal number pointing in each direction. An insulator is a compound which does not conduct electricity for all practical purposes. At extremely high voltages, a small amount of conduction will still occur. Conductor A conductor is a material which an electrical current will readily flow through. Conduction occurs either by the movement of electrons or the movement of ionic atoms or molecules.
Conductors always have a very small amount of resistance to electrical conduction.
Semiconductor A material that will conduct a small amperage of electricity when the voltage exceeds some critical value. This minimum necessary voltage corresponds to the energy necessary to excite electrons from a filled energy level called the valence band to an unoccupied energy level called the conduction band. This energy difference is called the band gap. Intrinsic semiconductors are materials which have a small band gap in their pure form. Superconductor Certain materials at very low temperatures will have a state with no resistance to electrical conduction.