These are tuned to work with MUDs and typically have separate windows for sending and receiving conversations. Many also support scripting and triggers, which allow you to automate responses to events occuring on the MUD - which is very useful for battle MUDs. Several MUD clients are now available for MS Windows. Once you have connected to the MUD, it will typically ask you for a name and password. If this is a game MUD, your login name will be a character name.
Some MUDs allow users to have multiple characters, each with different abilities.
After you've created a character, you'll be able to log onto the MUD again in future, typically taking up where you left before. You might also look for a map of the MUD, to give you an idea of the layout. Each MUD will have its own set of unique commands, but most have some common behaviors. Basically, a MUD is relational data base with a multi-user interface. The database stores objects which may represent spaces, players, behaviors and any other object in the database.