1. noun The human being sitting at a terminal or PC playing MUD, as opposed to their representation in the game (ie. their persona). In cases where the human being is so involved in the game that they feel it's really them in there, and that things are happening to them personally (ie. they are having fun), the player and persona can become one. In this case, the term player often subsumes that of persona. See also role-play.
2. noun A class to which those objects in the game that are assumed to be run by human beings belong, especially when compared against mobiles. There are technical reasons for this, arising from some of the Strange Things that wizzes are able to do.

Unless context indicates that a game object rather than a human being is implied, the first sense of player is the default usage of the term. A message in the game for 'all players', for example, does not mean that it is sent in the real world to all human beings playing at that moment, since it would actually only go to personae actually playing; however, to say it was sent to all personae implies the inclusion of any not actually in the game at the time. Therefore, in this example players would mean the all current instances of the class of player objects, ie. the second sense, rather than the first.