Sunlight

 Sunlight is a type of light that originates from the sun. It is composed of visible light, ultra violet radiation (U.V.) and infra red radiation (I.R.). Visible light makes up nearly half of the radiation received from the sun. I.R. is responsible for the heat produced from the sun and also makes up around half of the total radiation. U.V. makes up a very small portion of the total radiation, but produces vitamin D via the activation of ergosterol.