varVsLet.md

var vs. let

The difference about var and let has to do with scope.

Introduced in ES6, let allows to declare a variable that is accessible only inside a specific block of code.

Example:

function foo(){
  var a = 2;

  if(a > 1){
    let b = 4;

    while(b < 4){
      let c = a + b;
      b++;
    }
  }
}

In the example above, b can only be accessed inside the if statement and not in the whole foo function. Also, c can only be accessed inside the while loop.