Shell scripting

The Linux Documentation Project has an excellent (comprehensive) guide to Bash shell scripting http://en.tldp.org/LDP/abs/html/ For beginners, there is also the Beginner's Guide http://tldp.org/LDP/Bash-Beginners-Guide/html/index.html

Bash is the Bourne Again SHell, based on the original Bourne shell. Bash is the default shell interpreter on Linux (and Mac OSX). Other shell varieties include the Korn shell and C Shell, but Bash is the most common.