http://www.creativebloq.com/3d-tips/blender-tutorials-1232739
http://linuxnewbieguide.org/
http://www.ee.surrey.ac.uk/Teaching/Unix/
https://linuxacademy.com/howtoguides/linux
http://www.linux-pam.org/Linux-PAM-html/

http://www.linuxtopia.org/online_books/
http://www.onlineprogrammingbooks.com/linux/
http://freecomputerbooks.com/unixCategory.html