This page is private/ non bookmarkable. There is no way for any user to navigate to this page directly like it is possible with bookmarkable pages.
When navigating to this page, we passed the page that we came from as an argument. This page holds that as a variable, and uses it to navigate back to it when the user clicks the link beneath. Everytime a page is rendered, it is put in front of the list of pages that is in the session.