Light is considered to be radiation on a spectrum. To determine how much or little light there is, you would have to look at the light’s wavelengths. The wavelengths are measured in nanometers. Typically, the wavelengths of light range from four hundred to seven hundred nanometers. Infrared light has longer wavelengths and the ultraviolet light has short wavelengths.
There is a frequency range of wavelengths that are measured in terahertz. The range is between four hundred thirty to seven hundred fifty terahertz. The sun is probably the most common light on earth. Many people use the sun to see things in their dark houses instead of turning on the light. At night time, the sun can’t be used for light, so people must turn on a light.