People consider balanced and harmonious colour schemes to be pleasant. Colour harmony is created by contrast that defines space and helps identify and recognize objects within that space.
Analoguous colour harmony is easily achieved by selecting adjacent colours on the colour wheel, such as yellow, orange and red, or turquoise and green. Sometimes the starting point for interior decoration is the colour of the sofa upholstery for which matching wall paint should be found.
If we follow the principles of monochromatic harmony, we can choose a wall colour that is a lighter or darker hue of the colour of the sofa.
Different colours can also be combined based on hue identity by selecting, say, red and grey that have the same white and black content.
A pair of complementary colours provides a special effect by adding a suitable degree of tension and presence. Complementary colour pairs are yellow and violet, red and green, and blue and orange.