The YUV color space refers to the complete range of colors that can be displayed and recorded on digital video. The YUV color encoding system is used for analog television, such as NTSC and PAL.
The YUV colour space The reasons to use the YUV decomposition are multiple. Firstly, a conversion of an RGB signal (such as the one used on your monitor) to YUV requires just a linear transform, which is really easy to do with analogue circuitry and it is cheap to compute numerically.