title: PHP / javascript live chat using too much bandwidth
body: <p>So I am learning about javascript, so I am making a live chat system with PHP and javascript. I have it so the javascript refreshes the log (each message gets logged in a file on the server), and it refreshes every second. Im using firebug to monitor the resource usage, and I see under the net tab each times its updated, and the bytes add up really fast. I know I can change it to update less, but is there a way that when a user on the other end I'm talking to, when the send a message, it gets sent to the server, then an alert gets sent to me saying that the chatlog needs to update somehow. That way it only updates when the log is updated. let me know, thanks</p>