A twisted-pair cable is a cable made by intertwining two separate insulated wires. There are two twisted pair types: shielded and unshielded. A STP (Shielded Twisted Pair) cable has a fine wire mesh surrounding the wires to protect the transmission and a UTP (Unshielded Twisted Pair) cable does not. Shielded cable is used in older telephone networks, as well as network and data communications to reduce outside interference. The illustration gives an example of how the inside of these looks.