Shielded cables are electrical cables that contain insulating conductors encased in a standard conductive layer. The shield can be made from strands of braided copper (or a similar metal), a spiral copper tape, or some other conducting polymer. The importance of shielded cables cannot be stressed enough.
Shielded cables are usually thicker and more rigid than unshielded cables. They also require greater care when working with them. Shielded cables are most often found in industrial settings and installations where other nearby equipment is likely to generate electromagnetic interference (EMI).