How is a custom url desgined in a website?

How is a custom url for a page in a website designed? For example : AngularJS passing data to $http.get request

Two approaches to comes to my mind -

• Creating a folder in that location and putting the index.php which will get the question data.
• Creating a folder in that location and keeping a default index.php which redirects to question.php?questionid=xyz internally without changing the url in the browser.

I know above two approaches are not correct, but I couldn't find anywhere exactly how this is designed.