What are the ways to identify a URL is genuine or not, really part of the website or not. I mean when the domain part of the URL shows its that its ok.
For figurative example if we have to test URL if its part of a website forum.com . If the URL shows forum.com/engagements/ or if URL shows engagements.forum.com/ , or maybe engagements.forum.com/folder/folder/f, or
forum.com/engagements/file/ , or ... unlimited examples. Then how to know