The Linux System Administrator's Guide
"In the beginning, the file was without form, and void; and emptiness was upon the face of the bits. And the Fingers of the Author moved upon the face of the keyboard. And the Author said, Let there be words, and there were words."
The Linux-PAM System Administrators' Guide
Linux-PAM (Pluggable Authentication Modules for Linux) is a suite of shared libraries that enable the local system administrator to choose how applications authenticate users.
