Bash
From charlesreid1
Bash Guide
Using Bash
Setting the default shell: http://www.unix.com/shell-programming-scripting/32664-how-change-default-shell-linux.html
Startup Process
source /etc/profile
source ~/.profile
(source ~/.bash_profile?)
source /etc/bashrc
source ~/.bashrc
Dot Files
Bash Scripting
Looping
Looping in bash is really simple, and convenient - you can use other unix commands (most obviously "ls") to create lists, and then loop over each element of those lists. For example, if I want to print out the name of every file in my home directory (granted, not very useful, but this is just an example), I can do this:
for i in `/bin/ls -1 $HOME`; do
echo $i
done
Math
References
Floating point math in the shell:
http://www.novell.com/coolsolutions/tools/17043.html
Fast bash math:
http://www.bytemycode.com/snippets/snippet/350/
Bash script iterate through array of values
http://www.tech-recipes.com/rx/636/bash-shell-script-iterate-through-array-values/