It's usually a large outdoor light on the road/hookups side of the camper. Some larger units will have one on the door side also. It like a flood light / security light. Nice to have when setting up after sunset, or if your get "scared" by a bump in the night. Be kind to your fellow campers, and don't leave it on all night.
Chuck Roder & Family
'07 Surveyor SV-235RS & '03 Chevy TrailBlazer EXT LT V8
High Springs, FL.