What shape of sign generally indicates a warning?

A triangular shape sign is commonly used to indicate warnings on the road. This design is easily recognizable and communicates to drivers that they should be alert for potential hazards or changes in driving conditions ahead. The pointed apex of the triangle typically faces downward, reinforcing the need for caution. Triangular signs often forewarn about situations such as yield conditions, pedestrian crossings, or sharp turns. Their distinct shape helps them stand out among other sign types, making it easier for drivers to quickly understand that they need to reduce speed or take extra care.

In contrast, rectangular signs usually provide information or regulatory messages rather than warnings, such as speed limits or directional guidance. Circular signs often signify railroads or other specific situations and are not primarily used for general warnings. Lastly, pentagonal signs are used in association with school zones, indicating areas where children may be present, but again, they do not represent general warnings like the triangular signs do.