When we look at a thing, the eyes send information about the thing to the brain. Optical illusions help one to see a particular item very clearly. What we finally see does not depend on the inputs that our eyes give to the brain but the final image is perceived by the assumptions that are hidden in our brain. We tend to see an object the way we have seen it earlier. Optical illusions basically uncover the assumptions our brain has got about any particular object. One very good example of an outdoor optical illusion will be the camouflage which not only get used by the animals to protect themselves but the humans use the technique to design the army and military dresses in such manner that they could not be identified by their enemies easily. When we define camouflage in animals, we define it as a technique animals use to blend themselves with their environment but it is something more than the colors and patterns that are in front of us. It is about the visual assumptions that we have and it involves the concept of shading. Outdoor Optical illusions could make any backyard or surrounding area of a building look attractive and can catch the eyes of the onlookers. With a help from professional artists who are proficient in optical illusions drawings, the renowned brands are making use of optical illusions fro promotional activities. Having outdoor optical illusions will ensure that each inch gets utilized properly.