A stop sign is a traffic sign designed to notify drivers that they must come to a complete stop and make sure the intersection (or railroad crossing) is safely clear of vehicles and pedestrians before continuing past the sign.[1] In many countries, the sign is a red octagon with the word STOP, in either English, the national language of that particular country, or both, displayed in white or yellow. The Vienna Convention on Road Signs and Signals also allows an alternative version: a red circle with a red inverted triangle with either a white or yellow background, and a black or dark blue STOP. Some countries may also use other types, such as Japan's inverted red triangle stop sign. Particular regulations regarding appearance, installation, and compliance with the signs vary by some jurisdictions.