  This chapter gives an overview of interaction techniques for mixed reality
including augmented and virtual reality (AR/VR). Various modalities for input
and output are discussed. Specifically, techniques for tangible and
surface-based interaction, gesture-based, pen-based, gaze-based, keyboard and
mouse-based, as well as haptic interaction are discussed. Furthermore, the
combination of multiple modalities in multisensory and multimodal interaction,
as well as interaction using multiple physical or virtual displays, are
presented. Finally, interaction with intelligent virtual agents is considered.
