Back in the days it used to be simple. There was the Canon, and everything else was Fanon. But then along came the different media adaptations, the addendum made by the authors, the noncanon - often contradicting previous things, or each others - and the various Universe Bibles. Different fandoms have different ways of determining what's definitely officially part of the universe or not. Here's an index to help you.
Pages in category "Canon Universe"
The following 19 pages are in this category, out of 19 total.