aframe

A-Frame is an open-source web framework for building virtual reality experiences. It allows developers to create VR content with HTML-like markup that runs in web browsers. Built on top of three.js, it uses WebGL for rendering and interoperates with the WebXR API for immersive devices, while also providing fallbacks for non-VR environments.

The framework follows an entity-component-system architecture. Scenes are composed of entities such as a-scene and a-entity, and built-in components describe geometry, materials, lighting, animation, and interactions. Typical markup uses elements like a-scene, a-box, a-sphere, a-camera, and a-light, with attributes to set position, rotation, scale, and component properties. Developers can define new components in JavaScript, extending or combining existing ones to create custom behavior.

A-Frame includes a library of built-in components and a thriving ecosystem of community components, plugins, and templates. It provides the A-Frame Inspector, a browser-based editor that lets users edit properties and see changes in real time. It also supports VR controllers and gaze-based interaction, and can run on desktops, mobile devices, and standalone VR headsets.

The project is maintained as an open-source initiative, with a permissive MIT license. It is hosted on GitHub and has contributions from individuals and organizations across the web. Because it relies on standard web technologies, A-Frame experiences can be embedded in web pages and shared via URLs, facilitating easy distribution and experimentation.

Use cases include prototypes, educational demos, art installations, product visualizations, and web-based VR experiences. Its simple HTML-based syntax lowers the barrier to entry for web developers and designers looking to explore immersive content.