Chris G wrote:
I suppose there *is* a possible reason for this. If, say, user 'chris' wants to make his files available to other users then those other users can be added to group 'chris'. This is more specific than having to add them to group 'users' which would give them access to files of any user in group 'users'.
That's not a good idea, because that group has rights for *all* your files, not just the ones you want to share. So if you happen to have group-writable permissions on say your shell's dot files or executables in a ~/bin directory (not that you should), then your account can easily be hacked.
If you want to share files, the recommended way is to create a separate directory with appropriate permissions. See for example http://www.oreillynet.com/onlamp/blog/2006/09/using_user_private_groups.html .
-- Martijn