If you're confused on canon and fanon on this wiki, then this is the place for you!
Canon means anyone can use this character. This include all the teachers, and some OCs. All OCs are fanon by default but if you want it to be canon, just put it in the Canon Characters page. For a list of canon characters see the Canon Characters page.
This means only people with permission and the owner can use the OC. For a list of all fanon characters see the Students page.