Comparison of color models in computer graphics colors, "Printer's Colors" use cyan, yellow, and magenta, and "Light Colors" use red, green, and blue. "Light colors", more formally known as additive colors, are formed by combining red, green, and blue light. This article refers to additive colors and refers to red, green, and blue as the primary colors. Hue is a term describing a pure color, that is, a color not modified by tinting or shading (see below). In additive colors, hues are formed by combining two primary colors. When two primary colors are combined in equal intensities, the result is a "secondary color". A color wheel is
Green light source typically has a spectral power distribution dominated by energy with a wavelength of roughly 487570 nm. Human eyes have color receptors known as cone cells, of which there are three types. In some cases, one is missing or faulty, which can cause color blindness, including the common inability to distinguish red and yellow from green, known as deuteranopia or redgreen color blindness. Green is restful to the eye. Studies show that a green environment can reduce fatigue. In the subtractive color system, used in painting and color printing, green is created by a combination of yellow and blue,