There are two types of road warnings - temporary and permanent. Temporary warnings, typically due to construction, are in orange with black text (MUTCD Section 6F.02), while permanent warnings are in yellow for maximum readability and visibility. Orange has been widely used in road construction signs and other traffic control devices like cones, barrels, and delineators. In road construction, orange acts as an indicator for a driver because it is associated with roadside work. Fluorescent versions of orange may also be used.