Short presentation for my course "Fundamentals of Human-Computer Interaction" at the University of Leuven. Please note that I do not own copyright to the scientific paper itself. This research belongs to its rightful owners: Jeni Paay, Jesper Kjeldskov, Umachanger Brinthaparan, Lars Lichon, Stephan Rasmussen, Nirojan Srikandaraja, Wally Smith, Greg Wadley, Bernd Ploderer.