Highway signs can be thought of as a graphical user interface (GUI). Traffic signs depend to a large extent on very simple images that the motorist can comprehend quickly so as to be alerted to road hazards and potentially dangerous situations. The driver quickly recognizes that a sign with an arrow that curves sharply to the right indicates that the road will curve sharply to the right. Further, the graphics are standardized so as to refer to general types of conditions rather than the specifics of any particular highway or street because, with experience, the user can learn a limited set of standardized icons. This allows for more rapid comprehension and reaction than if the motorist had to contend with an infinite set of specialized diagrams unique to each specific situation. Nevertheless, there remains the possibility that the user, especially the less experienced driver, will misinterpret or misunderstand the visual imagery, in particular if icons are used to represent more complex or abstract concepts.