About the <script> tag

Use the <script> tag to implement JavaScript in a web page.

Set the type attribute to “text/javascript”

<script type=”text/javascript”></script>

Two ways to use the <script> tag

  • Container: the script tag contains JavaScript
  • External source: the script tag refers to an external file containing JavaScript

Script container

JavaScript code goes inside the <script> opening tag and the </script> closing tag.

Script source

Set the <script type=”text/javascript”> tag’s src (Source) property to a JavaScript file

<script type=”text/javascript” src=”somefile.js”></script>

JavaScript files

  • JavaScript files have the .js file extension.
  • JavaScript files contain only JavaScript.
  • JavaScript files do not contain the <script> tag; web pages contain <script> tags.

Where does the <script> tag go?

  • Must be inside <head> or <body> tag
  • Commonly found in <head> tag, or immediately before </body> tag
  • When using document.write method, <script> tag must appear in where want to write content
    — Avoid using document.write