JavaScript makes HTML pages more dynamic and interactive.
Try it Yourself - Examples
Insert a script
How to insert a JavaScript into an HTML document.
Use of the <noscript> tag
How to handle browsers that do not support scripting, or have scripting disabled.
The HTML <script> Tag
The <script> tag is used to define a script (JavaScript).
The <script> element either contains scripting statements or it points to an external script file through the src attribute.
Common uses for JavaScript are image manipulation, form validation, and dynamic changes of content.
The script below writes Hello JavaScript! into an HTML element with id="demo":
Example
<script>
document.getElementById("demo").innerHTML = "Hello JavaScript!";
</script>
Try it Yourself »To learn all about JavaScript, visit our JavaScript Tutorial!
The HTML <noscript> Tag
The <noscript> tag is used to provide an alternate content for users that have disabled scripts in their browser or have a browser that doesn't support client-side scripting.
The <noscript> element can contain all the elements that you can find inside the <body> element of a normal HTML page.
The content inside the <noscript> element will only be displayed if scripts are not supported, or are disabled in the user's browser:
Example
<script>
document.getElementById("demo").innerHTML = "Hello JavaScript!";
</script>
<noscript>Sorry, your browser does not support JavaScript!</noscript>
Try it Yourself »A Taste of JavaScript (From Our JavaScript Tutorial)
Here are some examples of what JavaScript can do:
JavaScript can change HTML content:
document.getElementById("demo").innerHTML = "Hello JavaScript!";
Try it Yourself »JavaScript can change HTML styles:
document.getElementById("demo").style.fontSize = "25px";
Try it Yourself »JavaScript can change HTML attributes:
document.getElementById("image").src = "picture.gif";
Try it Yourself »HTML Script Tags
| Tag | Description |
|---|---|
| <script> | Defines a client-side script |
| <noscript> | Defines an alternate content for users that do not support client-side scripts |
Test Yourself with Exercises!
Exercise 1 » Exercise 2 » Exercise 3 » Exercise 4 »