I find it frustrating that many things happen inside my Linux machine that I do not understand. If, like me, you want to really understand your system rather than just knowing how to use it, this document should be a good place to start.
Read it here
This HOWTO is can be found in doc-linux package on GNU/Debian in text and html formats.The Debian Documentation page lists an extensive list of manuals that are available to aid the learning the OS. Also visit the The Linux Documentation Project(TLDP) for more such HOWTO's , Guides and FAQ's.