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The Type and Language attributes of JavaScript

In this tutorial I'll explain the two main attributes of JavaScript that go inside the <script> tag, and their purpose.

The type attribute

In the tutorial JavaScript primer, I briefly mentioned the "type" attribute of JavaScript, and how it is used mainly so your JavaScript validates as part of a well form document. This is the reason why most JavaScripts written these days at least carry this attribute:

<script type="text/javascript">
//script here
</script>

Depending on the doctype you're using for your page, such as XHTML strict, adding the "type" attribute alone may still not cause the script to validate. In this case you can take it a step further, by declaring all contents of your script as a CDATA:

<script type="text/javascript">
<!-- <![CDATA[
//script here
// ]]> -->
</script>

Don't worry, this doesn't break the script in any way, as it's just JavaScript comments with additional code thrown in, and your JavaScript is sure to validate as a result.

The language attribute of JavaScript

The basic form of the language attribute is very easy to implement. Simply shove in the keyword "language=", followed by "JavaScript", into your <script> tag:

<script language="JavaScript">
alert("hi!")
</script>

This explicitly declares to the browser that your script is a JavaScript (instead of VBscript, for example). The "language" attribute while not essential to declare, is useful in certain cases. Lets talk about that next.