Three signals, luminance (Y) and two color difference signals R-Y (red minus luminance) and B-Y (blue minus luminance) which together carry the brightness and color information of color images . Color difference signals have no light intensity information, and cannot be displayed separately from Y. Compared to RGB signals, they can travel over longer cables lengths without significant resolution loss, and allows different spatial resolutions for luminance and color. Typically used for high-end visual applications. Also known as component signals. See also U and V signals.