Virtual Reality – The human perception of a digital, fully CG environment. In contrast to MR, VR makes no use of analog human experience but concentrates on computer-generated content for its UX.

Voice User Interface is a subdivision of UI – It describes the space where human-machine interaction takes place with voice. With the rise of Voice Assistants and the progress of AI-powered NLP, the use and the design of voice interfaces are getting more important.

Voice User Experience is a subdivision of UX – It describes the discipline of measuring and optimizing the personal experience of interacting with a product via voice interfaces.

Experience Design – Since every Design causes an experience: check out the term Design. Often used in the context of designing digital products.