If you are using JavaScript in your web application and you want to detect if JavaScript is disabled in the web browser and show error message accordingly.
In this case , you can add the <noscript> tag and show the warning message to the user accordingly.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Ginktage.com Home Page</title>
<script language="javascript" type="text/javascript">
document.write('Welcome to Ginktage.com JavaScript Tutorial');
// This is single line comment
/* This is a multi line comment 1
This is a multi line comment 2
*/
</script>
<noscript>
Sorry !!! You dont have JavaScript enabled on your browser.
</noscript>
</head>
<body>
</body>
</html>