How deep to dive into javascript

I'm a newish web dev using ASP.NET. I haven't really needed javascript for anything yet as the apps I've built so far have been fairly simple data mining apps and my audience aren't looking for bells and whistles. However, I'd like to start moving away from relying so heavily on ASP.NET's stuff (the built-in control validator开发者_如何学编程s, ajax toolkit, etc).

Aside from learning the language's syntax, what is essential to learn about javascript before I can start using frameworks like jquery to create meaningful business apps with nice ajax widgets etc? Would I need to learn all about the DOM and HTTP and different browsers?? All of that stuff is quite daunting

I'd spend at least a couple of hours experimenting with each of these:

1. DOM and environment (window, document, location, history, cookie)
2. Built-in types (numbers, booleans, arrays, objects, regexps)
3. Higher-order functions
4. Prototypes and constructors
5. Closures
6. Asynchronous execution (events, timeouts, xmlhttprequest)

I like Mozilla's documentation. It's correct, detailed and to the point. Learning these things will make you understand most of jQuery magic.