Red

Red is the color that is on the edge of the rainbow. It is one of the primary colors (colors that can be mixed with other colors) of light. The others are blue and yellow. Red light has a wavelength between 630 and 740 nanometers.

Red paint can be made by mixing yellow paint and magenta paint.

Red is sometimes used to mark things that are wrong, important or dangerous. It is also used as a warning to stop.