Client-side JavaScript (CSJS) is JavaScript that runs on client-side, i.e. the web browser, hence is for client-side scripting. While JavaScript was originally created to run on client-side, this term was coined because the language is no longer limited to just client-side, e.g. server-side JavaScript (SSJS) is also available.

Environment

The Internet media type for JavaScript source code is application/javascript, but the unregistered text/javascript is more frequently used.

To embed JavaScript code in an HTML document, it must be preceded with:

and followed with:

Older browsers typically require JavaScript to begin with:

and end with:

The comment markup is required in order to ensure that the code is not rendered as text by very old browsers which do not recognize the