CIE Standard Illuminants are a set of defined light sources used in color science to provide a consistent reference for measuring and comparing colors. Developed by the International Commission on Illumination (CIE), these illuminants represent different types of lighting conditions, such as daylight and artificial light, allowing for standardized color communication across various industries. Each standard illuminant is characterized by its spectral power distribution, which describes how much light is emitted at each wavelength. Common examples include CIE Standard Illuminant A, representing incandescent light, and CIE Standard Illuminant D65, simulating average daylight. These standards help ensure accurate color reproduction in photography, design, and manufacturing.