Before we proceed into the depths of color, let's first cover some of the basics.
Effective color communication depends on the proper use of language. All colors can be described in terms of brightness, saturation and hue. What exactly do we mean by that?

For the sake of convenience all possible colors can be fitted into the shape of a cone. The greys will be found on the axis. Upwards the colors become brighter, downwards they become darker. Towards the outside the colors become more saturated, in other words: less grey. All colors of the rainbow can be found in a circle around the axis. This model helps us to understand the meaning of the terms brightness, saturation and hue.

In the cone we can mark out a triangle. All the colors located on one triangle have the same hue. An orange has the same hue as fire, which has the same hue as a pineapple. Allthough pineapples generally are much darker than oranges. A leaf has the same hue as grass, which has the same hue as jade. The sky has the same hue as the IBM logo, which has the same hue as the mediterranean sea and a pair of jeans. Likewise, a banana has the same hue as a custard dessert and a lemon. Get the picture? All of the colours in the row below the cone are located on one triangle and have the same hue, even though some are more greyish, and some are darker than others. The row of colors below the previous cone all have a similar hue.

We can also mark out a belt with colors that all have the same distance to the axis. All the colors on the belt have the same saturation. Imagine having a pot of grey and a pot of red paint. The more red you add to the grey paint, the more saturated it becomes. Some people would say: it becomes more lively. The pot of red paint has a maximum saturation, the pot of grey paint has a minimum saturation. Replacing the red paint by a can of yellow, green or blue doesn't alter the saturation, it only changes the hue. All colors in the row below the cone have a similar saturation, even though they don't share the same hue or brightness.

In the cone a circular surface is marked out where all the colours have the same brightness. Brightness is related to the amount of light that is reflected by a color. Bright colors high up in the cone reflect a lot of light while colors down at the bottom reflect very little light and are therefor less bright. The row of colors below the cone all have a similar brightness.
In a next post I will offer some fun interactive exercises that will help you learn how to classify colors.