V7/usr/man/man5/group.5

Find at most related files.
including files from this version of Unix. 
.TH GROUP 5 
.SH NAME
group \- group file
.SH DESCRIPTION
.I Group
contains for each group the
following information:
.HP 10
group name
.br
.ns
.HP 10
encrypted password
.br
.ns
.HP 10
numerical group ID
.br
.ns
.HP 10
a comma separated list of all users allowed in the group
.PP
This is an ASCII file.
The fields are separated
by colons;
Each group is separated from the next by a new-line.
If the password field is null, no password is demanded.
.PP
This file resides in directory /etc.
Because of the encrypted
passwords, it can and does have general read
permission and can be used, for example,
to map numerical group ID's to names.
.SH FILES
/etc/group
.SH "SEE ALSO"
newgrp(1), crypt(3), passwd(1), passwd(5)