title: How to increment a counter each page load (in PHP)?
body: <p>I want a certain action to happen when a user has visited X pages of a site</p>
  
  <p>Do I have to store the counter externally (in a txt file or db)?</p>
  
  <p>I can't think of a way to set the counter to 0, then increment it each page load. The counter would always get reset to 0, or am I missing something obvious?</p>