Color possesses three attributes: hue, brightness and saturation. Their correlations can be illustrated by a three-dimensional color solid.

A color mode is a digital model that presents colors, serving as a way to record image colors. Common types include RGB, CMYK, HSB, Lab, Bitmap, Grayscale, Indexed Color, Duotone and Multichannel modes.

RGB is the most prevalent color mode, standing for red, green and blue primary colors. Each pixel occupies 3 bytes (8 bits per byte), corresponding to R, G, B color channels ranging from 0 to 255. It belongs to the additive color system, with 0 for pure black and 255 for pure white.

Features: Compact file size, rich and vivid colors.As a luminous color mode, it is widely applied for on-screen display, matching the operating principle of monitors.

Equal brightness values of the three primary colors form gray. Maximum value 255 of all channels creates pure white, while zero value results in pure black. Mixed colored light delivers higher brightness, hence this coloring method is defined as additive color mixing.