An e-mail address acts as a kind of marker of identity, and other kinds of interactions allow for other kinds of representation. At first glance, this relationship between gaming and social organization in the realm of the MUD might appear to be happenstance, but there are actually several reasons why games have often led the way in the development of computers. Games present a limited ruleset. Consider a grid. It would be easier to explain chess to someone from another culture than to explain why we shake one anothers right hands when we meet each other.
Games organize social dealings.
Games simplify these dealings, bringing them more into the foreground than they are in the culture at large. By enlarging and simplifying the roles the players assume relative to one another, the game allows us to experiment with these roles, providing a way of experimenting directly with very charged psychic material in a safe framework. The importance of a games rules transcend the game itself. Listen to a group of 8 year olds playing a game, any game. A huge amount of time and energy goes into arguing about the rules of the game itself, sometimes taking up more time than the playing of the game itself.