Normally, each line typed by a user is prefixed with their login id when it is displayed to others. Some channels can configured so that people can change their names, or to randomly assign names to users, or to give all users the same name. Or you can make it require that all users have unique names. You can set a default alias to be used in any channel that allows you to change your name. Users can be filtered out.
Users can read files into party.
Most channels set a line limit on that size of such files. You can also save lines from the party log into a file. Users can configure party behavior in many ways. You can also define arbitrary Unix commands as filters to feed all party output through. Idle users can be disconnected automatically.