Installing XDebug

 The first part of the instructions look like:

Download the Xdebug extension compatible with your version of PHP and save it in the php/ folder.

• The location of the php/ folder is defined during the installation of the PHP engine.
• If you are using an AMP package, the Xdebug extension may be already installed. Follow the instructions in the xdebug.txt.

Since I didn't install PHP I am not sure where the php/ folder is. I also don't know where xdebug.txt is or if I need to use it again since I don't know if this is an AMP package.

Hints?

Thank you