chrominance

In electronics, chrominance refers to the color component of a video signal, distinct from its brightness (luminance). It represents the hue and saturation of a color, providing the information needed for a color television to display an image in full color.12

Compatible color television systems, like the NTSC standard developed in the 1950s, transmit both luminance and chrominance information separately. The luminance signal carries the detail and is compatible with black-and-white televisions, while the chrominance signal adds the color information, which is largely ignored by monochrome sets. This approach efficiently uses the radio spectrum and allowed for the gradual introduction of color broadcasting without making existing black-and-white TVs obsolete.2