Differences in color are represented by "color temperature." Color temperature is a numeric value representing chroma rather than the temperature of the light source. All objects emit light when heated to an extremely high temperature. Color temperature indicates what color we would see if we were to heat up an object that reflects no light whatsoever, i.e. a "black body," to a certain temperature. The unit of measurement used in this case is degrees Kelvin. Low-temperature objects appear red, and as they heat up, they start to look blue. As you can see in the table below, the color temperature of reddish colors is low, while that of bluish colors is high. Color temperature is used for such purposes as setting the color on a computer monitor.