I come in contact with a lot of people who like to work with Linux and UNIX however find it hard to start. The GUI is not that hard however when they like to start working on the terminal things can get a little fuzzy. My girlfriend asked me a couple of days ago about how she could learn Linux command line interface commands and what a good guide could be. Well, the answer is here for all people speaking dutch. Go to the website of the University of Utrecht and checkout the page of Piet van Oostrum. He have published a great guide to UNIX.