Wikipedia:Content forks

A content fork is a piece of content (such as an inter-wiki object, a page, or a page section) that has the same scope as another piece of content that predated it, essentially covering the same topic. A content fork is acceptable or unacceptable depending on its type. Content forking is the act of creating a content fork. Transclusions are not content forks, because they do not diverge from the originals (usually templates).

As articles grow, editors are encouraged to create summary-style spin-offs or new, linked articles for related material, to make articles clearer and easier to manage.

While content forks that are different page types covering the same subject are acceptable, they should not contradict each other&mdash;contradictions should be corrected or removed.

When a content fork occurs by the creation of a pair of pages of the same type (such as two articles, or two templates, or two outlines) on the same subject, it results in two different versions of the same thing, which is unacceptable. The new page in such a pair is called a "redundant content fork". Content fork articles created unintentionally result in redundant or conflicting articles and are to be avoided, as the goal of a single source of truth is preferable in most circumstances. Therefore, it is important for an editor to check, before creating a new article on a particular subject, that there isn't already an article covering that subject.

A point of view (POV) fork is a content fork deliberately created to avoid a neutral point of view (including undue weight), often to avoid or highlight negative or positive viewpoints or facts. All POV forks are undesirable on Wikipedia, as they avoid consensus building, which violates one of our most important policies.

Etymology
The reason they are called "content forks" is that, like a software fork, even if one started off as an exact copy of another piece of content, the two pieces, being independently editable, may diverge over time, until they include different and possibly even conflicting facts about the topic.

Unacceptable types of content forks
While most types of content forks are acceptable, it is especially important to watch out for the unacceptable kinds...

Pages of the same type on the same subject
It becomes a problem when there are two articles about the exact same thing, or any two pages of the same type covering the same thing as each other, such as two outlines, two portals, two templates, two categories, etc. Imagine if 100 editors each wrote a separate article on the dog and Wikipedia displayed them all. That would defeat the collaborative purpose of the wiki, and it would make managing information on dogs 100 times more difficult.

A page that covers the same subject as another page of the same type is often called a "redundant content fork". The most common occurrence of redundant content forks results in two articles on the same thing; the extra one is a "redundant article fork".

Here are some examples of pages of the same type on the same subject:
 * An article about domestic house cats would be an unacceptable content fork of the existing article Cat (which is about domestic house cats).
 * An outline of the People's Republic of China would be an unacceptable content fork of the existing Outline of China (which is about the People's Republic of China).

Creating such forks can be unintentional or intentional. Although Wikipedia contributors are reminded to check to make sure there is not an existing article on the subject before they start a new article, there is always the chance they will forget, or that they will search in good faith but fail to find an existing article, or simply flesh out a derivative article rather than the main article on a topic. If you suspect a redundant article fork, check with people who watch the respective articles and participate in talk page discussions to see if the fork was justified. If the content fork was unjustified, the more recent article should be merged into the main article.

Redundant content forks of page types other than articles are rarer, but they do occur.

Note that "redundant content fork" is an idiom, not to be taken literally. All content forks are redundant, that's their nature, even the acceptable ones, but we use the term "redundant content fork" to refer to the specific kind described in this section.

Point of view (POV) forks
In contrast POV forks generally arise when contributors disagree about the content of an article or other page. Instead of resolving that disagreement by consensus, another version of the article (or another article on the same subject) is created to be developed according to a particular point of view. This second article is known as a "POV fork" of the first, and is inconsistent with policy: all facts and major points of view on a certain subject should be treated in one article. As Wikipedia does not view article forking as an acceptable solution to disagreements between contributors, such forks may be merged, or nominated for deletion.

Since what qualifies as a "POV fork" can itself be based on a POV judgement, it may be best not to refer to the fork as "POV" except in extreme cases of persistent disruptive editing. Instead, apply Wikipedia's policy that requires a neutral point of view: regardless of the reasons for making the fork, it still must be titled and written in a neutral point of view. It could be that the fork was a good idea, but was approached without balance, or that its creators mistakenly claimed ownership over it.

The most blatant POV forks are those which insert consensus-dodging content under a title that should clearly be made a redirect to an existing article; in some cases, editors have converted existing redirects into content forks. However, a new article can be a POV fork even if its title is not a synonym of an existing article's title. For example, if an editor has tried to include in an existing article about aviation a theory that heavier-than-air flight is impossible, but the consensus of editors has rejected the attempt as complete nonsense, that fact does not justify creating an article named "Unanswered questions about heavier-than-air flight" to expound upon the rejected idea.

The creator of the new article may be sincerely convinced that there is so much information about a certain aspect of a subject that it justifies spinning off a separate article. Any subarticle that deals with opinions about the subject of parent article must include suitably-weighted positive and negative opinions, and/or rebuttals, if available, and the original article should contain a neutral summary of the split article. There is currently no consensus whether a "Criticism of..." article is always a POV fork, but many criticism articles nevertheless suffer from POV problems. If possible, refrain from using "criticism" and instead use neutral terms such as "perception" or "reception"; if the word "criticism" must be used, make sure that such criticism considers both the merits and faults, and is not entirely negative (consider what would happen if a "Praise of..." article was created instead).

Acceptable types of content forks
Except for the types presented above, content forks are acceptable.

Note, that meeting one of the descriptions listed below does not preclude something from also being a POV fork.

Project-level content forks
There is a difference between article forking within Wikipedia and the legitimate practice of project-level forking. The latter occurs when someone wishes to create their own wiki, according to their own standards and practices, but they want to use Wikipedia's content as a starting place. As long as the new project adheres to their legal obligations under the CC BY-SA or GFDL in exchange for use of this content, as set out at Wikipedia's copyright policy, this is perfectly acceptable. Project-level forks are not bound in any way by Wikipedia's community policies or customs, like the five pillars. Project-level forking is discussed in more detail at Forking FAQ.

Pages of different types on the same subject
Content forks that are different page types covering the same subject are acceptable. Articles are not the only type of page on Wikipedia that cover subjects. Other subject-based page types include outlines, navigation footer templates, navigation sidebar templates, categories, portals, glossaries, indexes, lists, etc. Each type is designed to provide particular benefits. However, they, including corresponding articles, should not contradict each other, and any contradictory statements should be corrected or removed.

Here are some examples of pages of different types that cover the same subject:
 * Template:Geology, Template:Geology sidebar, Glossary of geology, Category:Geology, Outline of geology and Portal:Geology are all about the same subject, yet they are acceptable content forks of each other and of the article Geology, because they are all different types of pages.
 * Outline of sharks, Template:Shark nav, Portal:Sharks, List of sharks, and Category:Sharks are acceptable content forks of each other and of the article Shark.

Article spinoffs: "Summary style" meta-articles and summary sections
Sometimes editors "spin off" part of an existing article to create an article focused on a sub-topic. This is done through the Splitting process. Examples might be the cuisine of a particular region being forked from an article about the region in general, a filmography being forked from an article about a director, or a sub-genre being forked from its parent genre.

The main situation where spinoff articles become necessary is when the expansion of a section creates an undue weight problem for the article, for example:


 * Death of Michael Jackson was spun off from Michael Jackson.
 * O. J. Simpson murder case and O. J. Simpson robbery case were spun off from O. J. Simpson.
 * Jimmy Savile sexual abuse scandal was spun off from Jimmy Savile.
 * Multiple television-related media like the characters, the title sequence, and the music were spun off from Game of Thrones.
 * Multiple related tragic events like the timeline, the casualties, and the aftermath were spun off from the September 11 attacks.

The result is often an overview article written largely in summary style, e.g.:


 * Film
 * The Last of Us (franchise)
 * Physics
 * Uncharted
 * United States

Summary sections are used in a broader article to briefly cover the content of more detailed subarticles. Even if the subject of the new article is controversial, this does not automatically make the new article a forbidden POV fork. When done properly, the resulting articles are not POV forks, and both the original and the spinoff article will comply with the Neutral point of view policy.

See Article size, Splitting, and Summary style for procedural information.

Caution
Article splits are permissible only if written from a neutral point of view. They must not be an attempt to evade the consensus process at another article. On the other hand, having a separate article on a controversial incident may give undue weight to that incident. For this reason, Mel Gibson DUI incident was folded back into Mel Gibson (section), and Development of Uncharted 4: A Thief's End was folded back into Uncharted 4: A Thief's End (section).

However, there is a risk for article spinoffs to become POV forks. If a statement is inadmissible for content policy reasons at an article XYZ, then it is also inadmissible at a spinoff Criticism of XYZ. Spinoffs are intended to improve readability and navigation, not to evade Wikipedia's content policies.

Articles whose subject is a point of view (POV)
Different articles can be legitimately created on subjects which themselves represent points of view, as long as the title clearly indicates what its subject is, the point-of-view subject is presented neutrally, and each article cross-references articles on other appropriate points of view. Thus Evolution and Creationism, Capitalism and Communism, Biblical literalism and Criticism of the Bible, etc., all represent legitimate article subjects. As noted above, "Criticism of" type articles should generally start as sections of the main article and be spun off by agreement among the editors.

Related articles
Articles on distinct but related topics may well contain a significant amount of information in common with one another. This does not make either of the two articles a content fork. As an example, clearly Joséphine de Beauharnais will contain a significant amount of information also in Napoleon I of France; this does not make it a fork. Another example is where two articles cover the same topic, but are clearly directed at different audiences. In such cases, one of the articles will be prefixed by the text "Introduction to ...", for example General relativity and Introduction to general relativity.

Further, in encyclopedias it is perfectly proper to have separate articles for each different definition of a term; unlike dictionaries, a single encyclopedia article covers a topic, not a term. (cf. Wikipedia is not a dictionary)

Temporary subpages
One technique sometimes used to reach consensus on difficult articles is to create a temporary copy which people can then edit to show others proposed rephrasing or other changes. This can be helpful for controversial subjects or controversial changes; editors can show others exactly what their vision for a proposed change is – without the controversy of having that new proposed version automatically replace the existing version.

However, just as "spinout" articles have sometimes been mistaken for POV forks, temporary subpages have been mistaken for POV forks. Care should be taken on both sides to minimize such mistakes. New drafts should be written in the "Draft:", "User:" or "Talk:" namespace and not in the main namespace; however, accidents happen and those who think they have found a POV fork, in turn, should check to see whether the article title indicates a temporary subpage and whether the talk page of the main article indicates that this is a place to work on consensus rather than to dodge it.

List formats
Stand-alone lists can be formatted as tables or without using the table syntax. Tables don't work well on various devices (hand-held screens, omitted when using Wikipedia's PDF export function,... and the "sortability" advantage is lost in some cases). For that reason it is often a good idea to retain a structured list (or bullet list, or numbered list, ...) even when a table is provided with basically the same content. However, having two list pages with roughly the same content, one of them presenting the list content in a "sortable table" format, and the other not using table syntax for the list content, is only possible when: Also, provide a link to the differently formatted list high up on the page, preferably before the TOC or first section header, so that readers can switch to the other format if that works better for the device with which they are accessing the list. Example (see Naming conventions (music)): List of compositions by Franz Schubert (sortable table format) and List of compositions by Franz Schubert by genre (structured list).
 * 1) There is no other way to avoid a WP:PAGESIZE problem
 * 2) There is a true advantage to presenting the list as a sortable table
 * 3) It is worthwhile to put (usually considerable) maintenance efforts in two pages that roughly cover the same topic
 * 4) There is no notability issue for either of the pages

Tags

 * Template:Duplication
 * Template:Move portions and Template:Move portions from

Tools for automatic detection of content forks

 * WP:Duplication detector
 * Duplicate content report for en.wikipedia.org
 * Similar page checker to find duplicated content on two Wikipedia pages