[wruza]

I use var, together with let and const, where appropriate. What’s the problem with var I don’t get it.

[sandreas]

var is global scope, const is block scoped...

  <script>
  var x = 1;
  if(x < 5) {
    // now y is global (window.y can be accessed everywhere)
    // using const y = x * 2 would be inaccessible outside the if block
    var y = x * 2;
    console.log('double x is: " + y);
  }
  </script>

Besides that, var is "pulled" upwards, as if it was the first line in the function. That may have side effects.

[wruza]

I know how var works.

[sandreas]

No offense, just trying to help... :-)