MUSH stands for multi-user shared hallucinations -- or something. A MUSH is a server one can telnet to and play a text-based role-playing game (a bit like the Infocom ones, if you are, um, mature enough to remember them) on with other people. For some reason, MUSHes seem to attract people that care for language, experience, and generally encountering new situations, while MUDs (mult-user dungeons) generally seem to attract the hack & slay crowd. This might be due to the fact that MUSHes have next to no support for fighting, an often straining character creation process and generally less options for "winning the game". Certain stats may be raised, but this is not the objective of the game. MUDs have four basic modes of conduct:
OOC means "out of character", denoting all
that relates to you, the player (or actor), not your character (or role).
IC means "in character", denoting everything relating to the role (or character) you play.
If Harrison Ford plays Deckard in "Bladerunner", Deckard is the role or character, while Ford is the actor. If Emma Rhoids plays Buffy, the Vampire Slayer, Emma is the player/actor, while Buffy is the role. What Emma says as Buffy is in character; what Emma might say for herself about how she cannot finish the scene because she has to go to work to be able to pay the internet bill is out of character.
->Player Character (PC)
To play a character, like an actor does in a stage play. The
difference is, we don't normally work with scripts. We make up
our responses to situations as they occur. Situations are formed
by our own (player character) actions, those of
other player characters and those of non-player characters
controlled by players or staff. A good role-player would also take
things like setting, weather, mood, et cetera into account ---
we're "like writing this book together".
A minor part (or semi-attributed ("statted") character) in the drama of
the MUSH that is intended to enrich a given
situation in role-play. NPCs can be created by
players or by staff; they can be @created to physically exist as
an object (often @set PUPPET) in the MUSH database, or they can
be fully imaginary (using @emit). Shopkeepers, barmaids and
other sidekicks are normally NPCs.