Traffic warning sign is to pass specific information with graphic symbols and text, to manage traffic, indicating the direction of travel in order to ensure smooth traffic and traffic safety facilities. Applies to highways, urban roads and highways all dedicated, with a decree of nature, vehicles, pedestrians must comply. Traffic signs divided into the main and auxiliary signs mark two categories. Main flags warning signs, prohibition signs, directional signs and guide signs four. All traffic warning signs should be done properly position, accurate, complete, eye-catching and beautiful.