All light rays contain color. Light is made of electromagnetic waves. These waves spread out from any light source, such as the sun. Light waves travel at tremendous speed (186,000 miles or 300,000 kilometers per second). Different colors have different wavelengths, which is the distance between corresponding parts of two of the waves. The longest wavelength of light that humans can see is red. The shortest is violet. Ultraviolet has an even shorter wavelength, but humans cannot see it. Some birds and bees can see ultraviolet light. Infrared has a longer wavelength than red light, and humans can not see this light but can feel the heat infrared generates.