Two cables are required for a CCTV system, coaxial cable and power cable. Coaxial cable transmits video from the camera to a recorder. Power cable transmits electricity from a power source (for example an adaptor) to the camera.
Instead of purchasing a coaxial cable and a power cable separately or individually, a siamese type cable may be purchased. Siamese cable combines coaxial video cable with a power cable into one cable.