The differences between these three variables made me confused when I started to use ECMAScript 6. The most confusing was to understand the difference between let and var.
So let’s try to explain this difference.

var a = 'I am var';
const b = 'I am const';
let c = 'I am let';

What are the differences?
At first, let’s explain the concept of scope.
The scope is the fundamental concept in all programming languages ​​that defines the visibility of a variable.
The variables can be globals or locals.

To know the difference continue reading the article on Medium
https://medium.com/notonlycss/difference-between-var-let-and-const-in-es6-1d69f29586ff