WebGL
The browser's way of handing drawing work to the GPU.
See it in WebGL playground. Set Shape to Torus knot and drag to turn it.
In plain words
Web pages normally draw with the main processor, which is slow for big pictures. WebGL lets a page send its drawing work to the graphics chip instead. The page uploads shapes and pictures, then runs small shader programs on them. This is how 3D scenes, fluid simulations and live filters run smoothly in a browser. Almost every browser and phone supports it.