Opera Software's WebGL 101
Erik Möller from Opera software has posted (along with Co-author Chris Mills) a transcription a portion of his excellent WebGL 101 video tutorial (viewable on YouTube and embedded below)
The tutorial walks you through some of the basics of WebGL, what it is, what vertex and fragment shaders are and how to get some stuff on the screen.
For more, check out Opera’s Odin WebGL Showcase (which they demoed running in the browser on a tablet recently) and view the full 2 1/2 hours of WebGL 101 goodness below.