The Linux Documentation Project www.tldp.org

The Linux Kernel On-line book http://www.tldp.org/LDP/tlk/tlk.html http://kernelbook.sourceforge.net/

The Linux Virtual File System http://cgi.cse.unsw.edu.au/~neilb/oss/linux-commentary/vfs.html

Linux source code (Mirror sites if app) http://www.kernel.org/ http://www.kernel.org/mirrors/