eckertd

 Profile Answers by eckertd 

• Feb 5th, 2008

 

Unix groups provide a way to group together user accounts by function, role, department, etc.

A user belongs to a primary group, which is typically contained in the /etc/passwd file. 
A user may also belong to any number of secondary groups.  The /etc/group file contains group name, id, and the corresponding list of member user id's.

When you create user groups, you can modify file owner, group and permissions,such that all group members have the same access to files that pertain to that group.  For example, you may have a "dba" group that you don't want to have acces to files that belong to the "accounting" group.

See man pages for chown, chgrp and chmod for details on how to set file properties.