The SG-1/Atlantis/Universe canon refers to the Stargate universe depicted in Stargate SG-1, Stargate: Atlantis and Stargate Universe and the universe that this wiki is dedicated to. This universe is based on the one depicted in the Stargate film, but there are some differences. However, it is clear that the events depicted in the film did occur in the SG-1/Atlantis/Universe universe and elements of the film are considered canon so long as they aren't directly contradicted by the series.
There are many novels, comics, role playing games and other works set in this universe, meaning they use the characters and elements of the Stargate universe as seen in the SG-1/Atlantis/Universe canon to create storylines. Though the role-playing books and Fandemonium novels have been classified as canon,
the comics and ROC novels have not had an official word said either way and so it is unclear whether or not they are canon. In disputes between evidence seen on screen and information from other sources (even official ones, such as the MGM Tech Journal), the evidence on screen will always take precedence.
For further information on how to deal with canon on Stargate Wiki specifically, see our Manual of Style. For a list of canon, non-canon, and ambiguously-canon articles, see Category:Canon.