In orkut, as soon as one receives a new scrap, one gets an alert at side bottom even if page is not refreshed. I am sure that orkut doesn't check for scraps again and again by Ajax. Then how does orkut know that i have received a new scrap?? Similar thing is in shout boxes, whenever a new message is received they update automatically. Anyone know how it happens?

Orkut probably uses some server side push technology (maybe Comet). But shout boxes work by continually pinging the server for new posts. Normal AJAX. Well, most of them anyway.

Oh thank you jomanlk. The logic was simple enough and wasnt very tough to implement.

You're welcome, please mark the thread as closed