In Wiki, an Orphaned Topic is one without a real calling topic or category link. Orphaned topics can't be avoided, really, but it helps if you create new topics from a contextually related topic, and not from a scratch page (like Wiki SandBox or Scratch Pad).
An Orphaned Topic can be handy if you want to compose something new, but you're not quite ready to share it with everyone. Since there are no cross-references to it, it will show up only in the Recent Changes list. (Maybe we need a #NORECENTCHANGES directive, Steve.) Now, once you have it ready, you can go announce it from another page.)
The 2 ways I know to create one are: (1) hard way - reference the topic elsewhere so it gets created, then delete the reference; (2) easy way - type the new topic name in the URL! -- Randy Pearson