The steps in hue, value, and chroma, in the Munsell system correspond rather closely to our psycological concepts of equal steps in hue, brightness, and saturation. This is because the system relies on the judgement of observers looking at color samples illuminated by a standard light source.

The Munsell Book of Color is the method recommended for the "popular" identification of color.

The more technical CIE System is used to identify colors for scientific and technical purposes.