HSV Colour Model:

Rather than a set of colour primaries, the HSV model uses colour descriptions that have a more intuitive appeal to a user. To give a colour specification, a user choose a spectral colour and the amounts of white and black that are to be added up to obtain different shades, tints, and tones. Colour parameters in this model are hue (H), saturation (S), and value (V),

Figure: When the RGB Colour Cube is Viewed along the Diagonal from White to Black