group(5)
NAME
group − group file
DESCRIPTION
The /etc/group file contains for each group the following information:
•Group name
•Encrypted password
•Numerical group ID
•A comma separated list of all users allowed in the group
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.
This file resides in the /etc directory. 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.
FILES
/etc/group