Unshielded twisted pair (UTP) cables are made up of 8 internal wires and are the correct solution for most applications.

Shielded cables (STP) are used for increased protection from interference and crosstalk, they are typically used in electrically noisy environments.

Shielded network cables are usually used when running cables near any equipment or other cable that might cause interference with your signal. Common sources of interference are radio towers, high-powered electrical conduit, or any other device emitting electro-magnetic or radio frequency signals.