what is webgl ? code example

Example 1: what is webgl ?

WebGL is a JavaScript API for 
rendering interactive 2D and 3D graphics
within any compatible web browser without the
use of plug-ins. WebGL is fully integrated with 
other web standards, allowing GPU-accelerated usage of
physics and image processing and effects as part of the web page canvas.

Example 2: what is WebGL

enables web content to use an API based on OpenGL ES 2.0 
to perform 3D rendering in an HTML <canvas> in browsers 
use  shader code that is executed on a computer's Graphics Processing Unit (GPU)
elements can be mixed with other HTML elements and 
COMPOSITED with other parts of the page or page background.