title: What is php.ini and where it is located in CentOS
body: <p>I am new to php. I installed php on my <strong>CentOS 6.2</strong> machine. I have added an extension but when I install it I get a warning that I should add "<strong>extension=mongo.so</strong>" to php.ini.I cannot find php.ini. Just above that there is a warning that php_ini is not set to php.ini location. So php doesn't even know where it is. What is php.ini and where should it be located?</p>