Roleplay is about playing roles that are coherent with a setting, a set of rules and the community that makes these up.
It's easy to learn and play out when everybody's having fun and respecting the simple rules it implies. There's no such thing as good or bad roleplayers. It's a binary situation: either you're a roleplayer and you allow everyone to enjoy the game, or you're an autistic idiot that's living a fairy tale.
Simple mistakes and misunderstandings are irrelevant, since the objective is creating the history that's the continuous outcome of the game.
Edit to say: I disagree LigH. I've seen people new to roleplay doing a better job than most roleplayers that have been around for ages. Because of one thing: they came here to have fun and that objective is still fresh on their heads.
Some people think they've mastered something and end up ruining everyone's experience by acting god, when they can be mistaken as often as the other.
Guilty as charged!
