The page you are reading is part of a draft (v2.0) of the "No bullshit guide to math and physics."
The text has since gone through many edits and is now available in print and electronic format. The current edition of the book is v4.0, which is a substantial improvement in terms of content and language (I hired a professional editor) from the draft version.
I'm leaving the old wiki content up for the time being, but I highly engourage you to check out the finished book. You can check out an extended preview here (PDF, 106 pages, 5MB).
http://www.joshstaiger.org/archives/2005/07/bash_profile_vs.html
[ Safe mode ]
http://redsymbol.net/articles/unofficial-bash-strict-mode/
http://bytemuse.com/post/the-terminal-crash-course-and-reference-sheet/
bash usefulness
http://www.fizerkhan.com/blog/posts/What-I-learned-from-other-s-shell-scripts.html
[ robust scripts ]
http://www.davidpashley.com/articles/writing-robust-shell-scripts/
[ Shell scripting guide from google ]
http://google-styleguide.googlecode.com/svn/trunk/shell.xml#Indentation
links to resources to learn UNIX tools https://news.ycombinator.com/item?id=2415365
bash mistakes http://www.pixelbeat.org/programming/shell_script_mistakes.html
less common commans
http://www.danielmiessler.com/blog/collection-of-less-commonly-used-unix-commands
http://www.kfirlavi.com/blog/2012/11/14/defensive-bash-programming/