Javascript varable example

            <!DOCTYPE html>
<html>
<head>
<title>This is a page title</title>
</head>
<body>

<button onclick="function_name()">Sum!</button>

<script type="text/javascript">
function function_name() {
	var a = 5;
	var b = 6;
	var c = a + b;
	alert("The value of z is : " + c);
}
</script>
</body>
</html>
        

            
        