Coaxial Cable

A coaxial cable, also sometimes called "coax", is an electrical cable with an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by a tubular conducting shield.  The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis.  A coaxial cable is often used to carry signals from one instrument to another in situations where it is important to shield the signal from environmental noise sources.