Serious question(s). Answer please.

1. AU means Alternate Universe. So for example, let's say there was a... Drinny fanfic, except Ginny was in Slytherin and Draco was in Gryffindor. That is an AU, because it's different from the books.
2. Canon shipping is shipping such as Romione or Hinny, because that's exactly what happened in the books. Fanon shipping is the opposite. So basically, Romione is canon and Dramione is fanon.
3. Crack shipping is shipping somebody from one fandom with another person from another fandom. For example, like if you read The Hunger Games, it would be Hermione/Peeta, or something like that.