In the previous parts of this mini-course, we have devoted our attention to the hardware elements of the Lego Robotics Invention System and the question of how to control them using the accompanying software or a high-level programming language, such as Visual Basic. Naturally, it’s a lot more interesting to look at a real robot, and that is what we do in this final part.Describing components is of course informative, regardless of whether it is Lego blocks or the hardware and software that are used to build and control the models. However, really ‘playing’ is a lot more fun. Practical experience teaches that many people first make something, and only after that do they start looking at what is actually inside the RCX block, in order to see what else they can do besides copying the pre-cooked examples.