<html>
<body>
<h1>JavaScript Global Methods</h1>
<h2>The isNaN() Method</h2>
<p>isNaN() returns true if a value is NaN:</p>
<p id="demo"></p>
<script>
let result =
"Is '123' NaN? " + isNaN('123') + "<br>" +
"Is 'Hello' NaN? " + isNaN('Hello') + "<br>" +
"Is '2005/12/12' NaN? " + isNaN('2005/12/12');
document.getElementById("demo").innerHTML = result;
</script>
</body>
</html>