You're talking about ECMAScript 6 I suppose which is not official adopted as a standard and no browser fully supports it yet.

However, as Thomas pointed out, there are a number of cross-compilers that allow you to use it today. Unfortunately that's kind of a hassle as you have to effectively compile your JavaScript before it will run - either using command line tooling or with the help of converters offered by some tools like Visual Studio or WebStorm.

I also agree with Viv: Typescript might be the best way today to do ES6 and more importantly going forward to ES7 and beyond. Because these are transpilers that compile down to older versions of JavaScript (Babel and Typescript compile to ECMAScript 5), you get to play with new features of future versions today. Both Babel and Typescript support some features of ES7 already which is nice.

However, if you are new to JavaScript, there's a bit of a learning curve to get the tooling right. There are a lot of moving pieces. Module management, script loading, the transpilers etc all of which makes this stuff non-trivial to get started with. Plain JavaScript is a lot easier as it 'just works' in current browsers.

Be prepared to spend a bit of time learning if you go the ES6 route.

+++ Rick ---

>Anyone knows where I could get free documentation on the new implementation of javascript?
>
>I mean the Javascript can now have classes and lots of other nice things. I have old javascript books but I don't have the new additions to Javascript in those books.