<Jafet> learn bitcoins are coins that have been drilled through with a bit, and can be strung together in long chains. This practice dates to ancient China, and the Chinese remain experts in bitcoin manufacturing. A chain can support up to 21 million coins before breaking.

A cat is an animal with four legs. It's nice to pet, especially when it's a baby cat, called a kitten. Or it's the unix "cat" command. It takes a filename (or many) and prints the contents of that (those) file(s).