Color Theory is a set of principles used to create harmonious color combinations. Color relationships can be visually represented with a color wheel — the color spectrum wrapped onto a circle. The color wheel is a visual representation of color theory:
According to color theory, harmonious color combinations use any two colors opposite each other on the color wheel, any three colors equally spaced around the color wheel forming a triangle, or any four colors forming a rectangle (actually, two pairs of colors opposite each other). The harmonious color combinations are called color schemes – sometimes the term 'color harmonies' is also used. Color schemes remain harmonious regardless of the rotation angle.
The monochromatic color scheme uses variations in lightness and saturation of a single color. This scheme looks clean and elegant. Monochromatic colors go well together, producing a soothing effect. The monochromatic scheme is very easy on the eyes, especially with blue or green hues.
TThe analogous color scheme uses colors that are adjacent to each other on the color wheel. One color is used as a dominant color while others are used to enrich the scheme. The analogous scheme is similar to the monochromatic, but offers more nuances.
The Complementary Color Scheme consists of two colors that are opposite each other on the color wheel. This scheme looks best when you place a warm color against a cool color, for example, red versus green-blue. This scheme is intrinsically high-contrast.
The Split Complementary Color Scheme is a variation of the standard complementary scheme. It uses a color and the two colors adjacent to its complementary. This provides high contrast without the strong tension of the complementary scheme.
The Triadic Color Scheme is the most varied because it uses two complementary color pairs. This scheme is hard to harmonize; if all four hues are used in equal amounts, the scheme may look unbalanced, so you should choose a color to be dominant or subdue the colors.
The Tetradic (Double Complementary) Color Scheme is the most varied because it uses two complementary color pairs. This scheme is hard to harmonize; if all four hues are used in equal amounts, the scheme may look unbalanced, so you should choose a color to be dominant or subdue the colors.
Color theory analyzes only the relationships of pure colors; it does not take color lightness and saturation into account. While your color scheme can use any tints, shades, and tones, color theory pays attention only to the hue component.
Color theory analyzes only the relationships of pure colors; it does not take color lightness and saturation into account. While your color scheme can use any tints, shades, and tones, color theory pays attention only to the hue component. A century after Newton, Johann Wolfgang Goethe began studying psychological effect of colors. He noticed that blue gives a feeling of coolness and yellow has a warming effect. Goethe created a color wheel showing the psychological effect of each color. He divided all the colors into two groups – the plus side (from red through orange to yellow) and the minus side (from green through violet to blue). Colors of the plus side produce excitement and cheerfulness. Colors of the minus side are associated with weakness and unsettled feelings. The current form of color theory was developed by Johannes Itten, a Swiss color and art theorist who was teaching at the School of Applied Arts in Weimar, Germany. This school is also known as 'Bauhaus'. Johannes Itten developed 'color chords' and modified the color wheel. Itten's color wheel is based on red, yellow, and blue colors as the primary triad and includes twelve hues.