This special topic course introduces the principles and techniques used in extended reality (XR) technology. In the first part of the course, the base principles including computer vision, simultaneous location and mapping, object recognition, computer architectures, and XR frameworks will be covered. The course will then shift to application-level perspectives, including mixed reality interfaces, mobile input techniques, and user interaction. The course will be completed with hands-on practice through labs and projects leading to the development of a full XR application. Instructor’s approval is required.