While it's not specifically PHP-related, one of the new web tools that's been getting a lot of press lately (AJAX/XMLHttpRequest) is covered in this new tutorial over on the O'Reilly Network.

While not exactly new, the XMLHttpRequest object is receiving more attention lately as the linchpin in a new approach to web app development, most recently dubbed Ajax (asynchronous JavaScript and XML), which powers the cool features found on sites like Flickr, Amazon's A9.com, and the new poster children for whizzy web-based interactivity, Google Maps and Google Suggest.

Cool acronym or not, when I decided a while back to add a long overdue Search Playlist feature to my webcast radio station, EpiphanyRadio, it seemed like a good opportunity to show off some of the features the XMLHttpRequest object offers. The Search feature accesses a PostgreSQL database of the tracks in current rotation and allows listeners to search by artist, song title, and other criteria.

You'll need to have some knowledge of Javascript before you start (it's not a basic concept, but it's not overly difficult to use either) since he dives right into writing the request and making the XMLHttpRequest object for the connection. Once you've made the object, he shows you how to make the request and parse the server response.

Personally, I'm becoming more and more of a fan of this technology. I'm working up a little toolkit for PHP/Javascript coordination for some sites I'm working up, and it's coming in quite handy...