Why can functions be called using `` operator in JavaScript?

Question

Consider the following code:

<script>
  alert`1` // outputs 1
</script>

or

<script>
  function f($a) {
    alert($a);
  }

  f`2`; // outputs 2
</script>

Why does JavaScript allow functions to be called using `` instead of ()?

References like https://www.w3schools.com/jsref/jsref_operators.asp mentions nothing about the use of ``.

Can `` also be used to call functions that take more than 1 argument? If so, how?