i.e. red, orange, yellow, green, blue, indigo and violet... as well as the shades in between.
Spinning the disc mixed all the different wavelengths of coloured light together, creating white light. The faster you move the disc, the more white light you see. This process is call colour addition.
Colour subtraction occurs when substances that absorb light, such as paint, are mixed together. Mixing coloured paint eventually produces black paint, whereby all visible light is aborbed.