Creation Methods

<!DOCTYPE html>
<html>
<body>

<p>Click the button to create, and add, a comment to the HTML document.</p>

<button onclick="myFunction()">Try it</button>

<p id="demo"></p>

<script>
function myFunction() {
  var c = document.createComment("My personal comments");
  document.body.appendChild(c);
  var x = document.getElementById("demo");
}
</script>

</body>
</html>