Hue intensity (also known as saturation) is the purity or strength of a color. The intensity of a color is how bright or dull it appears and how close it is to the original color. The highest level of intensity a color can have is how it appears on the color spectrum or on a color wheel. A color that is reduced in intensity or purity is called a tone and is less bright than a color higher in intensity. The hue of red can range from pink to maroon to dark blood red. The highest intensity red is the one represented on the color spectrum. As it reduces in intensity it appears less bright and changes from bright red to a more dull red to pink colors. The lowest intensity of a color is when the hue is barely perceptible and appears to almost be the color grey.