Java script Basics

 Create alert box using Javascript

<html>

<body>

<h2>JavaScript Alert</h2>

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

<script>

function myFunction() {

  alert("I am an alert box!");

}

</script>

</body>

</html>

Alert box with TIMING

<html>

<body>

<h2>JavaScript Timing</h2>

<p>Click "Try it". Wait 3 seconds, and the page will alert "Hello".</p>

<button onclick="setTimeout(myFunction, 3000);">Try it</button>

<script>

function myFunction() {

  alert('Hello');

}

</script>

</body>

</html>