HTML JavaScript

JavaScript makes HTML pages more dynamic and interactive.

1. The HTML <script> Tag

The <script> tag is used to define a client-side script (JavaScript).

The <script> element either contains scripting statements, or it points to an external script file through the srcattribute.

Common uses for JavaScript are image manipulation, form validation, and dynamic changes of content.

To select an HTML element, JavaScript very often uses the document.getElementById() method.

This JavaScript example writes "Hello JavaScript!" into an HTML element with id="demo":

2. A Taste of JavaScript

Here are some examples of what JavaScript can do:

JavaScript can change HTML content

JavaScript can change HTML styles

JavaScript can change HTML attributes

3. 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 scripts:

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