The CIE chromaticity diagram is a graphical representation of colors based on human vision. It was developed by the International Commission on Illumination (CIE) to illustrate how colors can be perceived in terms of their chromaticity, which includes hue and saturation, but not brightness. The diagram maps colors in a two-dimensional space, where the x-axis represents the red-green spectrum and the y-axis represents the blue-yellow spectrum. In the diagram, each point corresponds to a specific color, allowing for easy comparison and analysis. The outer edge of the diagram represents fully saturated colors, while the inner area includes less saturated colors and shades of gray. This tool is widely used in fields like color science, photography, and display technology to ensure accurate color reproduction.