Final answer:
Signs with black letters on an orange background on highways indicate information and directions specifically for construction zones, enhancing driver safety by alerting them of changes in traffic patterns.
Step-by-step explanation:
On a highway, signs with black letters or symbols on an orange background provide specific information and directions to drivers in construction zones. These signs are part of a standardized system to alert drivers of upcoming changes or hazards on the road, specifically in areas where construction or road work is taking place. Recognizing these signs is crucial for maintaining safety, as they often indicate detours, closed lanes, or other temporary changes to traffic patterns.