Characters, programmed objects in the MUDs, are used as stand-in for players to interact with each other. Each player defines their own character's name, description, and any other relevant attributes. The co mmands that involve talking are called say commands and ones that involve action are called pose or emote commands. Action commands allow characters in the social MUDs to maneuver from chat room to chat room. Only m embers in the r oo m see the dialogue within each room .
Users can also interact with programmed objects within each room, such as chairs, boxes, or tables.
Action commands in MUDs that involve battling are more varied and complicated. There are also different classes of LP MU Ds that involve more complex programming languages, such as DikuMUDs and AberMUDs. Teachers, lawyers, and doctors can find MUDs that are created for members of their profession.