Each user belongs to one or more groups.  The only real importance of group relationships pertains to file permissions.

Group information is stored in /etc/groups in the format:
    groupname:password:GID:members

The password field is sometimes used to set a passwrod on group access.  This is seldom necessary.  To protect users from changing to privelegde groups with the newgroup command, set the password field to *.

Users should not be assigned (belong to) to groups like: bin, mail, sys, ...  They are for system file permissions.


to add a group, add a member to a group, delete a group, or remove a member from a group edit the /etc/group file