Color plays a vitally important role in the world in which we live. Color can sway thinking, change actions, and cause reactions. It can irritate or soothe your eyes, raise your blood pressure or suppress your appetite.When used in the right ways, color can save on energy consumption. When used in the wrong ways, color can contribute to global pollution.As a powerful form of communication, color is irreplaceable. Red means "stop" and green means "go." Traffic lights send this universal message. Likewise, the colors used for a product, web site, business card, or logo cause powerful reactions.The concept of color can be approached from several disciplines: art ,physiology, psychology,and philosophy.