Some terms you should know

The Hair-Dryer Corollary - I once saw a warning label on a hair dryer which read, in part, "Not intended for use under water". I use this example to explain how stupid people can be. It's a Hair DRYER. Its name should have clued in everyone that it shouldn't be used under water.

U-boat- This is a student answer that is so ridiculous. I publish these on Fridays. It started with this gem: "U-boats were like submarines, only different. They were boats that floated under the water. They had a telescope so you could see out. They helped the Germans greatly to defeat their enemas".