A-Frame web framework for Virtual Reality.

As originators of WebVR, the Mozilla VR team developed A-Frame as a web framework for building virtual reality (VR) experiences.
The core of framework provides an declarative, extensible, and composable structure to three.js.
You can find some example with this framework here.
The blog of the development team and users come with useful articles.
A-Frame supports most VR headsets:

• Vive
• Rift
• Daydream
• GearVR
• Cardboard
• ... and can even be used for augmented reality

The framework come with aframe inspector the online tool for visual tool for inspecting and tweaking scenes.
The Sonar Systems youtube channel come with some video tutorials about A-Frame VR framework: