title: Saving page ID within $_SESSION
body: <p>I am new to sessions, and think I get the basics of them, they seem to act like containers holding information which you can use on at a later stage and are linked to your UID.</p>
  
  <p>I am wondering how I would save the ID of a page (example ID123) on the click of a button, and what exact code I'd have in the header.</p>
  
  <p>Much appreciated in advance! </p>
  
  <p>EDIT:</p>
  
  <p>This is on wordpress, sorry to add this, each page has an 'event ID' I want this to be stored for use later (at a kind of checkout page) sorry for not adding this!</p>