>>32179408Canon is what's been established by official media. For example, it's canon that Pikachu is electric-type.
Headcanon is your own canon, something that applies to your universe but not necessarily someone else's. For example, Chicken is my headcanon SM protagonist, but that doesn't mean Sun can't be someone else's. A lot of people here seem to confuse canon with headcanon.
If a piece of your headcanon goes against something that's established in canon, it's canon-divergent. For example, you could have a canon-divergent headcanon that Lillie raised Pokemon while traveling in Alola. It conflicts with the canon but it's your universe so you can do whatever you want.
Hope that helped.
