Grayscale is an important basis for creating a color profile and calibrating a monitor so that images appear true to color.
They are formed from the 256 colors of an RGB color palette in which the red, green and blue components remain the same in the color value. If R, G and B have the value 0, the color defined by this is a pure black; if all three color components have the value 255, this defines a pure white.
This results in a gradation of different tones between black and white, each of which is identified by a number. An intermediate value, such as 192, defines a gray color of certain brightness. In the palette of a grayscale image, therefore, all 256 colors between 0 and 255 are stored − this means that a total of 256 possible gradations in brightness can occur. All color tones, which are stored accordingly between 0 and 255, result in the different gray tones.