This sort of utility would be perfect for a live support system for your website. The chat application we will be building today will be quite simple. It will include a login and logout system, AJAX-style features, and will also offer support for multiple users. We will start this tutorial by creating our first file called index.php. We start our html with the usual DOCTYPE, html, head, and body tags. We will now add some css to make our chat application look better than with the default browser styling.