Bedtime for Bonzo and The Life of Johnny Crapper

The Monkey treads forward bravely insinuating into the wide, wide, world of mattress sizing. Is a twin twice the size of a single? Is a queen twice the size of that? How many sizes are there and who in the world thought of these crazy names to begin with? The Monkey enlightens. Well, not really, but the Monkey does explain what the sizes are and where they came from. 

Also, indoor plumbing. Although it refers to sinks, faucets, showers, bathtubs and sink among other articles, the Monkey is focused on toilets. When did indoor toilets become a thing, where were they invented, and who has them? Is it only in undeveloped countries where it's hard to find these days? Let the Monkey help you with this puzzle.