Recently I decided to build part of a game that used an isometric projection for displaying the game board using HTML5.
Dirty plagiarist that I am, I found an excellent (albeit very old) tutorial by Danko Kozar for doing this. However it was written in Actionscript. No bother – I just modified the code to work in HTML5. This meant I could more or less ignore the theory of how isometric projection works and just get down to the business of doing it. Porting the code was easy. As it says in the tutorial:
These tutorials can be used for programming an isometric game in many programming languages not just in Flash. They are more about game programming than about Flash programming.