DOM Document

<!DOCTYPE html>
<html>
<body>

<h1>Document defaultView Property</h1>

<p>The defaultView property returns the current window object.</p>

<p>Click the button to demonstrate.</p>

<button onclick="myFunction()"> window object Before set to default  </button>
<button onclick="myFunction2()"> window object after set to default  </button>


<p id="demo"></p>
<p id="demo2"></p>

<script>
function myFunction() {
  var x = document;
  document.getElementById("demo").innerHTML = x;
}
function myFunction2() {
  var x = document.defaultView;
  document.getElementById("demo2").innerHTML = x;
}
</script>

</body>
</html>