Chris, the 6 digit rgb code consists of 3 distinct values. the first 2 figures refer to the Red value, the second to to the Green value and the third to the Blue value. each of these pairs can have a value of anything from 00 (or none) to ff (the hexadecimal equivalent of 255 or ALL). these values determine the amount of either red, green or blue in each rgb colour. what Chris was referring to as a pure colour means that the values that make green or yellow are cranked up, basically so pure green would be #00ff00 (no red, ALL green, no blue ), yellow would be #ffff00 (ALL red, ALL green no blue). does this help?