HTML is static - nothing on the page will change unless you edit it and post the changed page to your server. Scripting languages such as Javascript and PHP allow the appearance and content of the page to change dynamically through the use of special purpose HTML tags.

You can use a programming language such as Perl, Java, or C++, but unlike scripts, they can't be embedded in HTML, and must be accessed through a special "CGI" directory.

The links below will give you more information.