San Diego State University
Debian Tutorial
In general this tutorial tries to explain the reasons for things, and help you understand what's going on inside the system. The idea is to empower you to solve new problems and get the most out of your computer. Thus there's plenty of...
Other
Linux Powered: The Linux Kernel Howto
This is a detailed guide and FAQ to kernel configuration, compilation, upgrades, and troubleshooting for ix86-based systems.