redhat man page for group

GROUP(5)						     Linux Programmer's Manual							  GROUP(5)

NAME
       group - user group file

DESCRIPTION
       /etc/group is an ASCII file which defines the groups to which users belong.  There is one entry per line, and each line has the format:

	      group_name:passwd:GID:user_list

       The field descriptions are:

       group_name
	      the name of the group.

       password
	      the (encrypted) group password.  If this field is empty, no password is needed.

       GID    the numerical group ID.

       user_list
	      all the group member's user names, separated by commas.

FILES
       /etc/group

SEE ALSO
       login(1), newgrp(1), passwd(5)

Linux								    1992-12-29								  GROUP(5)