What is Extended Reality? A glossary

Extended Reality is a field with its own vocabulary — one that can feel opaque to business leaders approaching it for the first time. This glossary defines the core terms clearly and without jargon, so you can engage with the technology and the conversation around it with confidence.

Extended Reality (XR)

Extended Reality is the umbrella term for all immersive technologies that blend the physical and digital worlds. XR encompasses Virtual Reality, Augmented Reality, and Mixed Reality. It is the preferred term when referring to the broader field or to capabilities that span multiple modalities.

Spatial Computing

The broader technological paradigm in which digital content is integrated into three-dimensional physical or virtual space. Spatial computing includes XR hardware and software, but also the underlying technologies — computer vision, sensor fusion, 3D rendering — that make spatial interaction possible.

Immersive Technology

Any technology that creates a sense of presence — the subjective feeling of being somewhere, doing something. All XR technologies are immersive technologies, though the degree of immersion varies significantly across the spectrum.

Virtual Reality (VR)

VR Headset

A head-mounted display (HMD) that replaces the user’s visual field with a rendered virtual environment. Modern standalone VR headsets (such as Meta Quest) require no tethering to a PC and include built-in processing, tracking, and audio. PCVR headsets (such as Valve Index) connect to a high-performance computer for more demanding rendering.

Standalone VR

A VR headset that runs independently without a connected PC. Standalone devices use on-board processors and require only a WiFi connection for collaborative applications. Preferred for business deployment due to portability and lower setup complexity.

6DOF (Six Degrees of Freedom)

The ability to move freely in all six directions — forward/back, left/right, up/down, and rotation on all three axes (pitch, yaw, roll). Six degrees of freedom is the standard for modern VR headsets and is essential for natural, immersive interaction.

Room-Scale VR

A VR configuration in which the user can physically move within a defined space, with movement tracked and reflected in the virtual environment. Room-scale VR creates greater immersion than seated (stationary) VR, though it requires adequate physical space.

Augmented Reality (AR)

AR

Augmented Reality overlays digital content — images, text, 3D models — onto the user’s view of the physical world. Unlike VR, the physical environment remains visible. AR can be delivered through smartphone cameras, dedicated AR glasses, or head-mounted displays.

AR Glasses

Wearable devices that display digital content as an overlay on the user’s physical field of view. Current examples include Microsoft HoloLens and, more recently, Apple Vision Pro (which operates as a mixed reality device). True lightweight AR glasses remain an active area of development.

Spatial Anchoring

The ability to anchor digital content to a specific physical location so that it persists and remains correctly positioned when viewed from different angles or returned to later. Spatial anchoring is essential for AR applications in industrial, retail, and architectural settings.

Mixed Reality (MR)

Mixed Reality

Mixed Reality blends physical and digital environments in a way that allows digital objects to interact with — and respond to — the physical world. MR is more sophisticated than AR: digital content is not merely overlaid, but spatially aware of physical surfaces, lighting, and objects.

Passthrough

A feature on VR headsets that uses cameras to display a live video feed of the physical environment, with digital content composited on top. High-quality colour passthrough (as featured on Apple Vision Pro and Meta Quest 3) enables convincing mixed reality experiences without dedicated AR optics.

General XR Terms

Avatar

A digital representation of a user within a virtual environment. Avatars range from simple cartoon figures to photorealistic representations. In professional VR collaboration platforms, avatars convey head and hand movements in real time, functioning as the user’s social presence in the virtual space.

Presence

The subjective sense of being in a virtual environment — of “being there.” Presence is the defining characteristic of effective VR and is correlated with engagement, memory retention, and the quality of social interaction in virtual environments.

Haptics

Technology that simulates the sense of touch in XR environments. Haptic feedback ranges from simple vibration (standard in VR controllers) to sophisticated force-feedback gloves that simulate the resistance and texture of virtual objects.

Field of View (FOV)

The angular extent of the visual scene visible through a headset at any moment. Wider field of view creates more natural, immersive experiences. Current high-end headsets offer fields of view between 100° and 130°.

Refresh Rate

The number of frames rendered per second by a VR display, measured in Hz. Higher refresh rates reduce motion sickness and create smoother, more comfortable experiences. 90Hz is the current standard; 120Hz is increasingly common.

Usage and Applications

VR Collaboration Platform

Software designed for professional use within VR environments. Examples include Spatial, Immersed, Arthur, and Horizon Workrooms. These platforms provide virtual meeting rooms, whiteboarding tools, screen sharing, and avatar presence for distributed teams.

XR Training

The use of VR, AR, or MR to deliver training and skills development. XR training is particularly effective for procedural tasks (equipment operation, safety protocols), interpersonal skills (customer interaction, leadership), and scenarios that are dangerous or impractical to replicate in live settings.

Digital Twin

A real-time digital replica of a physical asset, process, or environment. Digital twins are used in industrial XR applications to visualise, simulate, and optimise complex systems without physical access to the asset.

Industry-Specific Terms

Enterprise VR

VR technology deployed for professional, commercial, or industrial use cases — as distinct from consumer gaming or entertainment applications. Enterprise VR typically prioritises reliability, security, manageability, and integration with existing business systems.

XR in Healthcare

The application of VR, AR, and MR technologies in clinical and medical training contexts. Applications include surgical simulation, patient-facing therapeutic VR (pain management, exposure therapy), and intraoperative AR guidance.

Immersive Learning

A training and development methodology that uses XR environments to create experiential, situated learning. Immersive learning consistently outperforms video-based and classroom-based approaches for knowledge retention and skills transfer in applied contexts.

WebXR

A web standard that enables VR and AR experiences to be delivered through a browser without dedicated app installation. WebXR lowers the barrier to entry for XR experiences but is limited in capability compared to native headset applications.