Apple Javascript (Script Editor) Documentation Is there a tutorial on how to use the documentation for Script Editor and Javascript?

I've been using AppleScript and Automator (with JavaScript) for a while but not extensively. I love how it works and what you can do with it. My problem is that I find very confusing the documentation (from Apple's website and from Script Editor's Library menu). I've been experimenting and doing stuff based mostly on examples.

I am familiar with PHP and Java Documentation which are great, is there some kind of easy to understand docs?
Apple has not updated their scripting documentation for JavaScript. The most recent documentation appears in the OS X 10.11 Release Notes - JavaScript for Automation.

There is extensive documentation for AppleScript in the AppleScript Language Guide.

MacStories has published a tutorial Getting Started with JavaScript for Automation on Yosemite.

Both this tutorial and Ash Ryan's Script Editor on Mac now lets you use JavaScript for automation mention a WWDC 2014: “JavaScript for Automation” which is probably the best place to learn more.