http://www.cyberciti.biz/howto/question/linux/dpkg-cheat-sheet.php
http://www.linuxquestions.org/questions/linux-software-2/what-is-the-command-to-delete-a-file-in-linux-terminal-290965/
http://www.debian.org/doc/manuals/debian-reference/ch01.en.html#_the_shell_prompt
