Answer:
It describes an era in history during which lights was hard to come by.
What do you call a snake that's exactly 3.14 feet long?
Why are teddy bears never hungry?
Why are football stadiums so cool?
If lightning strikes an orchestra who is the one most likely to get hit?
If you count 20 houses on your right going to the store and 20 houses on your left coming home, how many houses did you count?