Vision is the most important of the five human senses, since it provides over 85% of the information our brain receives from the external world. Its main goal is to interpret and to interact with the environments we are living in. In everyday life, humans are capable of perceiving thousands of objects, identifying hundreds of faces, recognizing numerous traffic signs, and appreciating beauty effortlessly. The ease with which humans achieve these tasks is in no way due to the simplicity of the tasks but is a proof of the high degree of development of our vision system.