Albert Henry Munsell was an artist and professor who created an accurate system for numerically describing colors, now known as the Munsell Color System in 19898. Using the previous colour theories Munsell extended the colour wheel into a three dimensional sphere to create a color space that specifies colors based on three color dimensions: Hue, Value & Chroma. Munsell determined the spacing of colors along these dimensions by taking measurements of human visual responses.
Hue – Is the specific colour measured by degrees around horizontal circles in the sphere
Value – Is the lightness or darkness of the colour measured vertically from 0 (black) to 10 (white) of the sphere.
Chroma – Refers to the intensity or purity of colour or the dullness (saturation) measured radially outward from the neutral (gray) vertical axis of the sphere