It says "if you are on PHP 5.3", only after reading this did I realize I already had PHP "installed" on my Mac（I think it comes with Mac OS) and this is where I got confused. I need something clarified:
1）I have XAMPP on my Mac, does its PHP interfere with what comes with Mac?
2) If I install Apache on my Mac, does it have its own PHP too? And after installing it, I will be able to use my Mac as a server right? What does this have to do with the server that is already running through XAMPP?
3)Back to what I was doing (installing xDebug), I think I need to install xdebug on xampp's PHP, but following this instructio, it seems to me that I will only install it to Mac's PHP. If this is true, how do I install xDebug to XAMPP?