The group is whatever group is associated with the file. The default in Fedora is that the default group of the user is also assigned to the user... which makes both group and user equivalent. Some systems (or those modified by the admin) may be given a default group that has multiple users. The group can be shown by "ls -l", which will show the symbolic representation of the owner/group and permissions (as well as the size of the file).
You can find some tutorial information at http://www.tutorialspoint.com/unix/u...permission.htm
on the symbolic/numeric representations.
The information is actually in the chmod man page, but not in an easily read format. It used to be there in a table, but I think that was back with the BSD man pages.. and has been rewritten since...
For some information on all the access bits (and there are more) you can look at the "man 2 stat" (the man page for the stat system call) which goes into detail on each bit, though it doesn't go into the symbolic representation as used by the ls command.