Click on the spectrum - colors. Watch RAINBOW painted on your screen. Try to create a more realistic Rainbow colors. To paint again go back to page. This applet does actually much more than simply drawing. It puts in "one-to-one" correspondence the One-parametric physical description of a color (defined by the wavelength, shown in a simplified scale below the spectrum) and the Three-parametric technical creation of colors by using mixtures of red, green and blue lights.The algorithm deals with very deep mathematical concepts related to numeration systems, and uniquely transforms two different presentations: of (+ , - 5) base-system and of 256-base technical system, into each other. This method is introduced in our activity "FALSE COINS" (see the Booklet) where with only one weighing one must find out all possible components of the selection.