3D Optical illusions are those visual illusions in which keep lots of brain functioning is tested. Actually these illusions are very different than what we perceive. The designs of the optical illusions are created in such a manner that these are able to trick our brains. These designs provide lots of visual information and compel it to see those designs in a different manner. The method of magic eye is used for creating these 3D Optical illusions. The viewers looking at these illusions must use parallel viewing in order to find out what the exact image is. Optical illusions seem mysterious to the viewers. They can stare at a pattern, group or cluster of images and suddenly they well find that a new image is appearing. For the viewers it appears as if the special effects jump out to them in 3D from that particular page but actually the brain is behind the entire thing and it is the brain that is responsible for this special effect. The optical illusions or mind games create three different effects. Firstly, they can create new images or objects from different objects e.g. small images of birds can give out the image of a man. Secondly, some optical illusions stimulate the brain with excess of light, color or tilt e.g. when black lines are positioned very closely the white spaces in between starts sparkling. Thirdly, some of these optical illusions are cognitive where the brain views at a particular object and makes inferences.