What is "Canon"?

This is not canon, sadly...

Canon is typically defined as any movie or television / streaming production of a given franchise, not including the subcategories of canon that follow.

Alpha Canon includes officially licensed print materials, such as movie tie-in comics, novelizations of canon productions, and the like.

Beta Canon includes productions licensed but not produced by the owner of a given franchise, such as novels and other published works of fiction and non-fiction.  Note, that Star Wars novels were generally accepted as Canon until the Disney acquisition of LucasFilm. 

For the sake of this guide, only official canon material is acknowledged.

Editor's Notes:

Is the Millennium Falcon in the Star Trek canonical universe?

The Official Star Trek Cannon fires Star Trek DVDs and is wholly ineffective as a siege weapon.