3D displays are now rapidly designed, enhanced and sold. It is expected that after a boom of displays based on active glasses, new display generations will appear. Those would be probably displays with passive glasses, multiview autostereoscopic displays based on parallax barrier or lenticular technology, and displays based on integral photography principles. Each of these types would be outperformed by holographic displays once they eventually mature. Holography is a concept known for a long time to opticians; however, for the computer graphics community it is a new undiscovered world. The tutorial provides basic principles of classical holography for people used to think in terms of rays instead of wave optics, and for those that have little experience with modern optics. These principles are then exploited in a talk about digital aspects of holography and about making holographic renderers. Every participant of the tutorial should be then able to make his or her own basic hologram renderer, to understand principles of advanced ones, and to build a very low budget holographic laboratory.