Many artists tend to be ignorant of, or ignore, the color theory. However, the color theory is an essential part of any art that you must know about. Do not ignore it, you will never become a good artist without understanding it.HistoryThe basic principles of color theory first appeared in the writings of Leone Battista Alberti(1435) and Leonardo Da Vinci(1490). The actual tradition of color theory, however, begins with Sir Isaac Newton who experimented with the colors and the origin of the colors in 1666.
Color WheelHave a look at the color wheel. We will be coming back to it later.
Basic TerminologyHue
Pure colors without any white, black or gray added.
Tint
A color with white added to it.
Shade
A color with black added to it.
IntensityBrightness or dullness of a color. (tint, shade)
SaturationPurity of the color. The closer a color gets to a hue, the more saturated it is.
Color GroupsThere are certain groups of colors that can be used to get pleasing results.
MonochromeThis involves different shades and tints of the same hue.

Here is an example of a monochrome tag-
ComplementaryThis combination involves colors on opposite ends of the wheel.

Other variations of it are double- and split- complementary, which we won't be discussing here.
TriadsThey involve three colors placed at equal distances from each other. The best example would be primary and secondary colors.
Primary Colors | Secondary Colors |
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AnalogousInvolves colors placed adjacent to each other. It is very similar to monochrome.
ConclusionHope you enjoyed this tutorial. In this tutorial you learned the basics of the color theory. If you don't get it at first, don't be disheartened and feel free to ask questions.
Other Interesting PlacesDonnaYoung.org - Exploring Color TheoryWorqx - Color Theory TutorialColorJack - Color Theory Visualizer (has many other interesting color tools as well)