There are three basic levels of baseband video signal interfaces. In order of increasing quality, they are composite (or CVBS), which uses one wire pair; Y/C (or S-video), which uses two wire pairs; and component, which uses three wire pairs. Each wire pair consists of a signal and a ground. These three interfaces differ in their level of information combination (or encoding). More encoding typically degrades the quality but allows the signal to be carried on fewer wires. Component has the least amount of encoding, and composite the most.
Composite Video – It combines luminance and chrominance leads into single yellow RCA jack, which is common on PC and home. It gives decent video quality.
S-video – It combines the two chrominance signals into one and uses a mini-DIN of various pin counts. It has one luminance and one chrominance (C) output lead and a ground for each.
Component Video – It performs a signal-splitting function by creating luminance (Y) signal and two color difference signals known as Pb and Pr, to approximate the original RGB signal.