
The Harry Potter Wiki will, thus, present some facts, histories, and even entire characters that did not appear in the Harry Potter books as canon.Harry Potter is an urban fantasy saga by J.K Rowling. It has been noted that the fundamental difference between these two approaches are shift in the burden of proof, that is, the Lexicon expects details from the films to have to be proved canon, while the Wiki says they have to be proved not canon. Rowling has said or written: ergo, any information that comes solely from the films or video games is automatically non-canon and disregarded. This approach contrasts with another prevalent attitude towards canon in the Harry Potter fandom, which is the Harry Potter Lexicon approach: basically put, it has been the Lexicon's policy ever since it was created in 1999 to consider that canon consists only of the things J. Rowling herself as the highest forms of canon information from the films is regarded as canon only provided it does not conflict with the books (video games and other officially licenced material is placed on a third tier, below the films). This "canon tier" system regards the novels and sources that come from J. The Harry Potter Wiki, starting in 2007 when it defined the wiki's canon policy, has employed a novel approach to canon by assigning different levels of canonicity to different media.

Though it is widely accepted in the Harry Potter fandom that the seven original novels take canonical precedence, the opinions of fans on the canonicity of other "official" materials (such as Harry Potter and the Cursed Child, the Fantastic Beasts series, or even the author's Twitter revelations) differ, at times significantly. Unlike what happens in some other fandoms with multiple "official" works or original media, most notably Star Trek and Star Wars, what constitutes canon within the Harry Potter franchise has never been officially defined.

Main articles: Canon and Harry Potter Wiki:Canon
