Light pollution occurs when there's too much light in the atmosphere invading the clearness of the sky. It is also known as photo pollution, because of the word ‘photo' which means light. It is excess or obtrusive light created by humans, excess of artificial light that reduce visibility of stars. We, humans, do things without realizing the consequences, but they say too much of a good thing is bad. There's nothing that is 100% right, it has the right side and the wrong side as well. We all need light, but we use too much which results in light pollution. Light pollution includes sky glow, glare, light trespass and artificial lights. I am going to explain these three types of light. The first one is LIGHT TRESPASS, it occurs when unwanted light enters one's property for instance, by shining over a neighbor's fence or yard. The second one is GLARE; it is often the result of excessive contrast between bright and dark areas in the field of view. The third one is SKYGLOW; it is the combination of all reflected form what it has illuminated. Sky glow increase night sky brightness and reduce visibility of stars. Astronomers are very worried about this because they are ...