How to provide a pair of users with same website content

I am designing a game, where two users at a time are provided with same questions one after other. However each user has to wait until the other user also answers that particular question. Once both 开发者_StackOverflowthe users answer that question, they will be displayed with new question simultaneously. I would like to dos this preferably in PHP,AJAX etc.. technologies as i can get free servers with these technologies. Some help on how to achieve this is appreciated.

I'd check into Comet or a similar open-connection method (otherwise you're stuck with setInterval polling or something similar). PHP may or may not be a good fit, depending on your deployment... possibly relevant discussion here:

Using comet with PHP?