A quick overview of new JavaScript features in ES2015, ES2016, ES2017, ES2018 and beyond. Let function fn () { let x = 0 if (true) { let x = 1 // only inside this `if` } } Const const a = 1 let is the new var. Constants work just like let, but can’t be reassigned. See: Let and const
![ES2015+ cheatsheet](https://cdn-ak-scissors.b.st-hatena.com/image/square/fe1b663ad14c695604261638b61f0edad49642fd/height=288;version=1;width=512/https%3A%2F%2Fassets.devhints.io%2Fpreviews%2Fes6.jpg)