Server log files are usually kept here.

What they're used for:

checkpt.log:
        Database saves are recorded here.

command.log:
        Logging of SUSPECT player activity and other command logging.

connect.log:
        All connections and disconnections are recorded here.

netmush.log:
        General server messages and errors.

trace.log:
        Memory allocation stats and errors are recorded here.

wizard.log:
        Logs of game-altering things done by wizards, and things done TO
        them.
