Coaxial cable, also known as coax, is an electrical cable that consists of an inner conductor surrounded by a concentric conducting shield, with the two separated by a dielectric. Coaxial cable is used as a transmission line for radio frequency signals and is used in applications such as telephone trunk lines, broadband internet networking cables, high-speed computer data busses, cable television signals, and connecting radio transmitters and receivers to their antennas. The key to coaxial cables success has been its shielded design, which allows the cables copper core to transmit data quickly, without succumbing to interference or damage from environmental factors. Coaxial cables have concentric layers of electrical conductors and insulating material, which ensures signals are enclosed within the cable and prevents electrical noise from interfering with the signal. Coaxial cables are primarily used for sending audio and video signals and are integrated into complex video relay and distribution systems. The most common types of coaxial cables used in video applications are RG59/U and RG6/U. Coaxial cables are also used for carrying internet signals, and RG-6 cables are used for this.