Codecademy, an interactive tutorial on the basics of JavaScript, has attracted 200,00 unique users in just three days.

Want your time spent noodling around with idle games to actually bear fruit? Bitburner is an incremental-style idler that casts you as a terminal cowboy on the world wide web, hacking, stealing ...

If you want to learn to create relatively simple online games using Javascript, then the HTML5 Game From Scratch Step By Step Learning JavaScript course is a great place to start.