The practicum "Augmented, Mixed, and Virtual Reality" in Module inf174 ("Special Topics of Media Informatics and Multimedia Systems") introduces basic technologies and paradigms of Augmented Reality (AR), Mixed Reality (MR) and Virtual Reality (VR). In the first few weeks, students practically learn about tracking methods, 3D / 2D display and interaction of virtual objects, current display devices (such as Microsoft Hololens), and software (such as Unity). A hands-on project starts in week 3, where students will plan and implement a mini-research project in the field of AR / MR / VR in small groups (~ 3). Students will develop a prototype based on current research questions in the AR/VR field. The planning phase is followed by an approximately 6-week development phase, which ends with the evaluation of the prototype. The results of the project will be presented in a final presentation.