title: "Proper" separation/difference between index.php and front controller
body: <p>For a PHP MVC application, what is the difference of the job of the <code>index.php</code> file and front-controller? Is the front-controller in the <code>index.php</code>, or is it in a separate file? How do I separate the two and let them work together? Is the front-controller supposed to be a class (or like its own entity)? (If that's the case, then index.php will instantiate the front-controller?)</p>
  
  <p>I know that they have to "set up the environment," which includes defining some constants and etc, but what does what? (-- autoloader, debug stuff, etc.)</p>
  
  <p>I have seen this: <a href="https://stackoverflow.com/questions/19868206/mvc-with-a-front-controller-confusion">MVC with a front controller confusion</a>, but that doesn't solve the problem of the difference between <code>index.php</code> and the front-controller.</p>