I am a newbie at web programming. I have basic PHP programming skills.
From what I understand about PHP is, it runs on the server side and generates a HTML code, server-side PHP script ends, and then that generated HTML code is sent to us (us = browsers of the clients). But in some webpages (programmed with PHP) which I encounter on the internet, the server-client interaction keeps running silently at the background even a long time after the page had completed loading.
For example, in the Stack Exchange communities, when I am viewing new questions I see that the vote counts are changing (as other users vote) without refreshing the page. This indicates that a background script is communicating with a database, right?
Are these kind of pages implemented by pure PHP?
If yes, I thought PHP script had to finish at the server side before the generated HTML code to be sent. What is the secret of this method?If no, what additional programming languages and/or web technologies do I have to study to learn it? Do they combine another technologies with PHP?
Please guide me on this.
