Before we get to World of Warcraft though, let's pause to learn from Raph Koster. Raph is no stranger to MMOs, as he was the design force behind Ultima Online and Star Wars Galaxies. He wrote an excellent book called A Theory of Fun that you all should read. I tend to put "fun" in quotes, because it's a pretty nebulous thing that I don't know how to define. Fun is like pornography; I know it when I see it. Raph was brave enough to attempt an explanation of "fun."

Fun is learning in a safe-environment.

Those few words have a lot of implications. Games are mini-worlds where we can try out all sorts of ideas and possibilities, and see what works and what doesn't. Games let us fail with little penalty and then let us try again. Games teach us how to time our jumps, how to aim, how to solve puzzles, and how to manage resources. They teach us strategy: when to attack, and when to avoid a fight. It would be great if they taught a wider range of lessons, but as Raph says, that's up to us game designers to make it happen.