passwd(5)
NAME
passwd − password file
DESCRIPTION
The /etc/passwd file contains the following information for each user:
•Name (login name, contains no upper case)
•Encrypted password
•Numerical user ID
•Numerical group ID
•GCOS job number, box number, optional GCOS user ID
•Initial working directory
•Program to use as Shell
This is an ASCII file. Each field within each user’s entry is separated from the next by a colon. The GCOS field is used only when communicating with that system, and in other installations can contain any desired information. Each user is separated from the next by a new-line. If the password field is null, no password is demanded. If the Shell field is null, the Shell itself is used.
Because of the encrypted passwords, it can and does have general read permission and can be used, for example, to map numerical user ID’s to names.
FILES
/etc/passwd