Component video cables take the concept of separating signals a step further than S-Video cables.  Where S-Video cables separate the video signal into color and luminance or brightness, component video cables divide the signal into red, green, and blue.  These are the primary colors of the audio/video world.  Every other color displayed on your television or computer monitor is a mixture of these three.  Since each of these colors no longer has to share the same path with the others, more information pertaining to each can be sent with fewer errors and distortion.
    The RCA connectors of the component video cable are denoted with the color that each transmits and the connection on your home theater components are similarly color coded.  The entire home theater industry follows this color code standard.