Example: if you go to a video on YouTube.com and click "Show comments in real time" (or something like that), the comments start to show in real time. How do they do this and how would I be able to efficiently duplicate this feature (preferrably using PHP and JavaScript)?
Thanks!
If you mean what I think you mean, and it's similar to the way facebook will load comments on posts etc 'as soon' as they are posted, then it's using AJAX to load the new comments, and Javascript and PHP to create a new HTML element with the comment in it. To my knowledge there is no real way of making this happen other than to continuously look for new comment, but it could be a JavaScript to look for a new comment every 10 seconds, or every time an event fires....