NIS (Network Information System) in the current name for what was once

known as yp (Yellow Pages). The purpose for NIS is to allow many

machies on a network to share configuration information, including

password data. NIS is not designed to promote system security. If

your system uses NIS you will have a very short /etc/passwd file with

a line that looks like this:

+::0:0:::

To view the real password file use this command "cd/etc;ypcat passwd"