ajax im ("asynchronous javascript and xml instant messenger") is a browser-based instant messaging client.

It uses the XMLHTTPRequest object in JavaScript to send and receive commands to and from the server. No refreshing of the page is ever needed for this "web application" to work, as everything is updated in real-time via JavaScript.

The XMLHTTPRequest object allows HTTP requests to be sent to the server and get input back from the server. There are two parts to the client-server interaction through this object.

1. The client "pings" the server (a PHP script) for new messages. The server in turn queries a database for any messages for the client, and returns them as JSON. The XMLHTTPRequest object passes this JSON text be parsed by the rest of the JavaScript.
2. The client sends data to the server (a PHP script), such as a new message to another user. This data is then processed by the server ("cleaning" the data of anything invalid) and put into the database, which is later "pinged" by another client.

In essence, ajax im simulates a "persistent connection" relationship using only the HTTP protocol and periodic requests.

Browsers that ajax im has been tested on and works:
- Mozilla Firefox 1.5.0.6
- Internet Explorer 6
- Internet Explorer 7
- Opera 9.00
- Safari

Updates:

• Major overhaul of the code: everything (PHP and JS) is now object-oriented instead of procedural


• Many functions modified to make better use of the Prototype library 


• Multiple language support (need translators!) 


• PHP-based sessions implemented, so the username and password isn't sent on every message request 


• Buttons no longer separate images; buttons are now boilerplate images + text 


• Proper theming system -- themes are bundled into folders instead of all over the place 


• New dark theme! 


• Buddylist database structure converted to be in a separate table 


• Ability to block/unblock users 


• Userlist added, now displays all users in a chatroom 


• Room list added to the "join room" dialog 


• Basic (beta) admin panel added. Supports searching for users, banning, kicking, and making/removing admin