Which is the simplest way to add ES6 to a Rails 5.1 app?

Hi! As of Rails 5.1.4, which is the most simple way to use ES6 in a Rails application?

If you write your Javascript using webpacker, it will use ES6 out of the box.

For the asset pipeline, there's a sprockets-es6 gem.

I've heard about ES6 recently but I'm a little confused.

What is ES6 and what is the benefit of using it in Rails?