Canon (fiction)

In fiction, canon is the material accepted as officially part of the story in an individual universe of that story. It is often contrasted with, or used as the basis for, works of fan fiction. The alternative terms mythology, timeline, universe and continuity are often used, with the first of these being used especially to refer to a richly detailed fictional canon requiring a large degree of suspension of disbelief (e.g. an entire imaginary world and history), while the latter two typically refer to a single arc where all events are directly connected chronologically. Other times, the word can mean "to be acknowledged by the creator(s)".
Influential or widely accepted fan theories may be referred to as "fanon", a portmanteau of "fan" and "canon". Alternatively, the term "headcanon" is used to describe a fan's own interpretation of a fictional universe.
Origin.
The use of the word "canon" originated in reference to a set of texts derived from Biblical canon, the set of books regarded as scripture, as contrasted with non-canonical Apocrypha. The term was first used by analogy in the context of fiction to refer to the Sherlock Holmes stories and novels, written by Sir Arthur Conan Doyle, as contrasted with numerous Holmes adventures added later by other writers. This usage was afterwards extended to the writings of various other authors.
Canonicity.
When there are multiple "official" works or original media, the question of what is canonical can be unclear. This is resolved either by explicitly excluding certain media from the status of canon (as in the case of "Star Trek" and "Star Wars"), by assigning different levels of canonicity to different media (as was in the case of "Star Wars" before the franchise was purchased by Disney), by considering different but licensed media treatments official and equally canonical to the series timeline within their own continuities universe, but not across them, or not resolved at all. The use of canon is of particular importance with regard to reboots or re-imaginings of established franchises, such as the "Star Trek" remake (2009), because of the ways in which it influences the viewer experience.
The official "Star Trek" website describes "Star Trek" canon as "the events that take place within the episodes and movies" referring to the live-action television series and films, with ' having long existed in a . Events, characters and storylines from tie-in novels, comic books, and video games are explicitly excluded from the "Star Trek" canon, but the site notes that elements from these sources have been subsequently introduced into the television series, and says that "canon is not something set in stone." Some non-canonical elements that later became canonical in the Star Trek universe are Uhura's first name Nyota, introduced in the novels and made canonical in the 2009 film "Star Trek", and James T. Kirk's middle name Tiberius, introduced in the "Star Trek" animated series and made canonical in '.
During George Lucas' time with the franchise, "Star Wars" canon was divided into discrete tiers that incorporated the Expanded Universe (EU), with continuity tracked by Lucasfilm creative executive Leland Chee. Higher-tier and newer material abrogated lower-tier and older material in case of contradiction. The live-action theatrical films, the 2008 and its , and statements by Lucas himself were at the top of this hierarchy; such works invariably superseded EU material in case of contradiction. The EU itself was further divided into several descending levels of continuity. After Disney's acquisition of the franchise, Lucasfilm designated all Expanded Universe material published prior to 25 April 2014 (other than the first six theatrical films and the 2008 "The Clone Wars" film and TV series) as the non-canonical "Legends" continuity. Material released since this announcement is a separate canonical timeline from the original George Lucas Canon, with all narrative development overseen by the Lucasfilm Story Group.
The makers of "Doctor Who" have generally avoided making pronouncements about canonicity, with Russell T Davies explaining that he does not think about the concept for the "Doctor Who" television series or its spin-offs.
Additional works.
In literature, the term "canon" is used to distinguish between the original works of a writer who created certain characters and/or settings, and the later works of other writers who took up the same characters or setting. For example, the canon of Sherlock Holmes consists of the 56 short stories and four novels written by Sir Arthur Conan Doyle and featuring the detective Sherlock Holmes. The subsequent works by other authors who took up Sherlock Holmes are considered "non-canonical".
Other writers.
Some works by the original writer such as "The Field Bazaar" but not the same publisher may be debated as forming part of canon. This is because copyright used to be exercised by the publisher of the work of literature rather than the author.
However, sometimes in literature, original writers have not approved works as canon, but original publishers or estates of original writers posthumously approve subsequent works as canon, such as "The Royal Book of Oz" (1921) (by original publisher), "Porto Bello Gold" (1924) (by estate), and "Heidi Grows Up" (1938) (by estate).
Late 20th century.
In film and television this is common that the original writer does not decide canon. In literature, the estate of H. G. Wells authorised sequels by Stephen Baxter, "The Massacre of Mankind" (2017) and "The Time Ships" (1995). "Scarlett (Ripley novel)" was a 1991 sequel to "Gone with the Wind" authorised by the estate.
21st century.
Sequels to the stories by P G Wodehouse about the butler Jeeves were sanctioned by Wodehouse's estate for "Jeeves and the Wedding Bells (2013)" by Sebastian Faulks and "Jeeves and the King of Clubs (2018)" by Ben Schott.
Fanon.
Fan fiction is almost never regarded as canonical. However, certain ideas may become influential or widely accepted within fan communities, who refer to such ideas as "fanon", a portmanteau of "fan" and "canon". Similarly, the jargon "headcanon" is used to describe a fan's personal interpretation of a fictional universe.