12 volt RGB (red, green, blue) lighting has a common 12 volt input which in most cases is the black wire. The red, green and blue wires connect to ground for corresponding color channels. RGB lighting is practically universal and is perfect for lighting accent areas. RGB lighting falls short in reproducing white. It recreates a white color, but due to the gaps in the visible spectrum it does not produce a “true white”. This means the color of objects viewed under this light look different than they would under day light or an actual white LED.  In technical terms: RGB reproduced white light has a “low CRI”, (Color Rendering Index). This is the reason that all SHADOW-CASTER lights used for general illumination have a true white channel. Also, all SHADOW-CASTER lighting controllers will support both RGB and RGBW. Where this “W” indicates support for a “white” LED channel.