Mac OS X,  Mac OS X Server

Mac OS X: Groups with Leading Underscores

Have you noticed all those groups in Mac OS X with names that start with an underscore (_)?  What do they mean?  Well, that’s just the naming convention in 10.5 for service accounts.  So in most flavors of *nix you would have an lpadmin group but in OS X you now have _lpadmin instead.  Nothing sinister or weird, just a naming convention.