This is a repo that demonstrates the different ways to use ES6 modules and how Babel can be used to transpile these into different formats that work in browsers today.
I'm using it in my talk at this event and will hopefully have a link to the event soon. The slides can be found here
Be aware that Babel has to do some stuff to get its job done that may mislead you a bit (and this can lead to tears. It's always good to understand the specification:
MIT