Seat belt - Jerry Seinfeld

maydang.blogspot.com - "Airline hostesses show you how to use a seat belt in case you haven’t been in a car since 1956."

This person is trying to give advice to the person who even doesn't know the meaning of A. You can say that a person who can not afford to have fan at home, is getting tips on how to operate air-condition at home. So when someone is doing such a silly thing, you can instantly punch this joke.