As you probably already know, colours on your computer screen can be described in terms of their red, green, and blue components. By mixing these levels of these colour components you can generate millions of different colours. Still another way to look at colour is in terms of hue, saturation, and brightness.

 

Hue refers to how we perceive the dominant wavelengths of a colour source. Simply put, hue is the characteristic we are describing when we refer to a colour as green, or purple, or red. In a sense, you could think of hue in the same way that you think of shades or tones of colour. Some people use the word hue in the same way they would use the word colour.

 

Saturation refers to how we perceive the ratio of the dominant wavelengths to all the other wavelengths of a colour source. In other words, Saturation can be described as the strength or intensity of a shade or tone of colour. A colour that is very saturated will appear strong and vivid to our eyes, while a colour that is much less saturated can appear to be washed-out or weak. A colour that is completely desaturated will appear as a shade of grey.

 

Brightness refers to how we perceive the amount of light energy given off by a colour source. People often think of brightness on a scale from dark to light, with black having very little brightness (light energy), and white having maximum brightness.

 

As it turns out, any of the colours that can be described in terms of red, green, and blue values can also be described in terms of hue, saturation, and brightness values. Some people find that the hue, saturation, and brightness scheme is a more intuitive and natural way to view colour than the RGB scheme.