Auto Ajax is a PHP class that can be used to update only parts of pages when links are clicked, using AJAX to avoid full page reloading. It uses some JavaScript code to intercept the clicks on the current page links. The link clicks trigger AJAX POST requests to fetch the content to update specific page sections, instead of the whole page. If the browser does not support JavaScript or AJAX requests, the clicks on the links will make the browser retrieve the whole page as usual.