Nine Basic Shapes You Should Know
The basic shapes and colors of traffic signs are important.You should know signs by their appearances so when driving you can recognize them at a distance even when visibility is poor. If snow covers a sign, the shape can help you decide the most likely meaning of the sign.
There are ten colors and nine basic shapes of traffic signs. Each shape and each color has an exact meaning. You should learn all of them for your DMV examination.
In some states, you should expect one or two questions about shapes and colors on the knowledge test. Pay special attention to signs that have exclusive use, like the sign that warns of a railroad crossing ahead, the stop sign, and the yield sign.