Image Recognition is another extremely important technology for self-driving which helps achieve a true understanding of the environment, because it is the only way to see indicators such as traffic lights, brake lights, and turn signals. Image recognition can be broken down into two rough categories: machine vision and computer vision. Machine vision is simpler in nature, referring to things like finding particular features (edges, corners, etc.) detecting motion, motion parallax, and using stereo vision to estimate distance. Computer vision is the much harder problem of recognizing objects and understanding what they are doing. The way this currently works is through machine learning techniques in which a large training set can be used to teach an AI (Artifical Intelligence) to recognize and understand something. That's really cool, but there is still a long way to go before these techniques reach the level of accuracy necessary for a commercial vehicle and can be trusted to know what they do in an scenario.