How Wikipedia Works/Chapter 8

=Chapter 8: Building Wikipedia's Web=

In Chapter 3, Finding Wikipedia's Content, we described many ways to browse Wikipedia. For instance, readers can explore Wikipedia via the links between pages or through categories of related articles. If an area of Wikipedia has been worked on for long enough, these browsing journeys go smoothly. But Wikipedia's content does not start out perfectly linked or classified, and new articles need to be integrated with existing content. Articles need care and attention to become fully usable in the context of the rest of the site.

This chapter turns to web-building techniques on Wikipedia. You can add to, alter, and mend Wikipedia as a piece of hypertext. We'll cover six concepts for building navigational structures, linking articles, and maintaining article organization. These concepts have been mentioned in previous chapters, but here we'll present them as editorial tools.

First, we'll cover redirecting one page title to another and building disambiguation pages, both of which help readers navigate, avoid duplication, and search the site more productively. We'll then focus on how articles are combined, split apart, or moved to better titles in order to comply with style guidelines and to make them more useful for the reader. In the next section, we'll discuss categories and categorization, which help readers navigate similar topics and editors maintain sets of pages. Finally, we'll review community processes for resolving problems that arise related to these topics.

Redirect and Disambiguate
Redirects and disambiguation pages, first described in Chapter 1, What's in Wikipedia?, play important roles in internal Wikipedia connections. A redirect page directly points the reader from one page title to another and is used when more than one possible page title exists. Disambiguation pages clarify the use of a keyword by pointing to all of the articles that are referred to by that term or a similar term.

Redirects
If you go to the article Norma Jeane Mortenson, you'll be automatically taken to the article called Marilyn Monroe instead.

Although a reader doesn't see it, a page does exist under the title Norma Jeane Mortenson, but not a regular article page. Instead, this page is a special, very short page that only contains a pointer to another target page. This page is a redirect, Wikipedia's equivalent of an index entry reading for Norma Jeane Mortensen, see Marilyn Monroe.

A redirect can be set from any page to any other page. Redirects are often used for name variants and common misspellings for people, places, or things. Although the article can only exist under one title, redirects automatically take the reader to the actual article from any conceivable title that he or she might search for. Redirects make it easier to find and search for content because they also show up in search results.

Wikipedia has a tremendous number of redirects. As of mid-2007, the site had more redirect pages than article pages, by somewhere between 5 percent to 10 percent. Historical figures, with their varying names, titles, and multiple spellings, are a prolific source of redirects. Other significant sources are Romanizations of names and terms from other languages. For instance, English does not have a standard way for writing Arabic names: Mohammed, Mohammad, and Mohamed are all accepted ways of writing the Prophet's name. All of these possible spellings redirect to the actual article title (currently Muhammad), saving the reader the trouble of figuring out which spelling variation to use.

As a small part of its mission, Wikipedia has to manage this huge system of redirects and disambiguations. Many reference works face this issue. For instance, an article in The Economist in 2007 talked about the problems confronting government intelligence agencies as they reconcile name variations:

""One of our biggest problems has always been variations of names," says Michael Scheuer, who was the head of the CIA's Osama bin Laden Unit from 1996 to 1999. Mr Scheuer says analysis was "backbreaking," especially for Arabic names, because it involved manually compiling lists of variations deemed worthy of tracing."

Wikipedians know how Mr. Scheuer feels. Names matter to reference works, but names are complex. Previous reference works and printed encyclopedias dealt with the problem by developing See references to guide readers from one term to another in an index; Wikipedia, which doesn't have a printed index, has an automatic—and much more comprehensive—solution instead.

Redirects are also helpful when two pages with the same content are merged together, as described later in Section 2.1, "Merging Articles". When two pages are merged, the result is a composite article at one of the page titles and a redirect from the other one.

Creating and Editing Redirects
You can easily create new redirects. First create a new article using the title you want to become a redirect, as described in ../Chapter 6/, "Good Writing and Research". Then type only this text on the page:


 * 1) REDIRECT title of page to redirect to

For instance, if you want to redirect the page Goldfishes to the article Goldfish (although article title convention uses the singular form of nouns, readers may search using the plural), you would create the page Goldfishes and type this text:


 * 1) REDIRECT goldfish

Then add an appropriate edit summary (rdr is common shorthand for redirect) and click Save. Now, if a reader tries to go to the page Goldfishes, he or she will instead end up at Goldfish. As a bonus, if a link to the page Goldfishes also appears somewhere in another article, when a reader clicks that link, he or she will be taken to Goldfish.

You don't have to start an entirely new page to create a redirect. If the page Goldfishes already exists, you can turn it into a redirect by replacing any existing text with the redirect code and clicking Save. Be careful, though; if an article is already on the page, you may want to move it to a better title or merge it with an existing page, as described later in Section 2.1, "Merging Articles".

If something goes wrong (or you change your mind), you can always edit a redirect. A redirect, like any other change you make to the site, can be reversed. But how?

Suppose Erik Weisz is a redirect to Harry Houdini, following Wikipedia's practice of titling articles about performers using their most common stage name. If you follow a link to Erik Weisz, you'll be redirected to Harry Houdini; but don't get frustrated! When you are taken to an article from a redirect, you'll notice the title of the redirected page is displayed below the page title, showing you how you got there (Figure 8.1, "A redirect title below a page title—Harry Houdini, redirected from Erik Weisz").

Figure 8.1. A redirect title below a page title—Harry Houdini, redirected from Erik Weisz A redirect title below a page title—Harry Houdini, redirected from Erik Weisz

Click the linked page title (Redirected from Erik Weisz) to access the redirect page itself (Figure 8.2, "A redirect page for Erik Weisz").

Figure 8.2. A redirect page for Erik Weisz A redirect page for Erik Weisz

When you access an actual redirect page, you'll see a special URL, similar to https://en.wikipedia.org/wiki/Erik_Weisz?redirect=no. Adding  after the page title in the URL prevents the page from automatically redirecting.

You can then edit this redirect page like any other page, either to change the redirect target or to remove the redirect and start an article instead. You can also check the page history for the redirect page to make sure quality content wasn't accidentally lost when the redirect was created.

Here are some reasons for viewing and editing redirects:


 * Create a full article at the page title to replace the redirect to another page. (This often happens when articles about similar or related items all redirect to one central page; specialty articles may eventually be written about each item.)


 * Change the redirect to point to a different page (for instance, if the redirect was not quite right or had a typo).


 * Revert the creation of the redirect if the page contained content before the redirect was created, so you can restore an earlier version (for instance, if the redirect was created accidentally or restoring the original article is important).


 * Copy content from an earlier version of the article (before the redirect was created) onto some other page (you can find previous versions by browsing the redirect page's history).

Limitations on Redirecting
Redirects are not always called for. For instance, you shouldn't create a redirect to an article that doesn't exist yet unless you plan to write that article immediately. Creating a redirect in this instance is detrimental: It creates a useless dead end, and it turns the redirect page title into a bluelink, whereas a redlink might attract the attention of an author who would want to write the article. For a similar reason, when articles are deleted, redirects to them should also be deleted.

You should also be careful when creating redirects to sections in an article. For example,


 * 1) REDIRECT Ice cream

is the text for a redirect page for Vanilla ice cream; it takes you to the Vanilla section of the page Ice cream. Section-specific redirects are useful, but they are not robust. This redirect could be broken easily by an editor retitling the section Vanilla flavor (Wikipedia has no way for you to discover What Links Here at the section level). For this reason, the Manual of Style recommends leaving a hidden comment, for instance, below the section heading when you redirect to it (see w:WP:MOS).

One recurring theory is that you shouldn't pipe links to redirect titles. In other words, some Wikipedians think pilot of the first manned flight is worse than pilot of the first manned flight, given that Orville Wright redirects to Wright brothers. If the Wright brothers were given separate articles one day, however, the piped link to Orville would have been a better choice. As long as you don't create double redirects, you can create links to redirects. Some cases are discussed in depth at Wikipedia:Redirect. The point, generally, is to help readers rather than distract them.

Finally, two technical issues limit redirect creation.

Double redirects
Avoid creating a redirect to a redirect: The database software is unable to forward twice. You can check for double redirects by clicking What Links Here; for instance, if you create a redirect by moving a page, check What Links Here for the old title. As the page mover, you're responsible for updating any redirects to point to the new title.

Redirects across namespaces
Redirecting from one namespace to another is confusing because the whole point of namespaces is to separate different types of content. With a few exceptions, redirects should stay within one namespace. If a list page is replaced by a category, a redirect from the list page (in the main article namespace) to the category (in the Category namespace) could be created. Users may redirect their user pages to their user talk pages (from the User namespace to the User_talk namespace). A Wikipedia: namespace help page may be redirected to an existing help page in the Help namespace. Articles in the main namespace should not redirect to other namespaces, however. For more, see Wikipedia:Cross-namespace redirects (shortcut WP:CNR).

Disambiguation Pages
Disambiguation pages, colloquially known as dab pages, are one of the Wikipedia success stories. Their assigned role is humble enough. Many phrases or single English words are ambiguous because they have multiple meanings. Take, for example, the word bridge. Besides being a structure that allows you to cross over a river or other obstacle, bridge can be a card game, a piece of dental work, or the command post of a ship. With all these meanings, wikilinks to the article Bridge could often lead readers to the wrong article. The solution is to create several differently titled articles for each meaning of the ambiguous term along with a dedicated page to link to, or disambiguate, between all of them for readers.

Note: Wikipedia coined the term disambiguation early on in its history because the site needed a word for pages that served this function.

If only two or three articles may be confused, a lightweight form of disambiguation are hatnotes (see ../Chapter 4/, "Understanding and Evaluating an Article"), which point back and forth between two or three articles. For terms with more meanings, a dedicated disambiguation page works better.

In this case, the disambiguation page is located at Bridge, which lists the possible articles that may be related to the term bridge. As of January 2008, this page included links to the following articles:


 * Bridge, a fixed prosthesis used to replace missing teeth.


 * Bridge, the area from which a ship is commanded.


 * Contract bridge, the modern card game; see Bridge for other card games that bridge may refer to.


 * Bridge, an interlude that connects two parts of a song.


 * Bridge, a structure built so that a transportation route can cross an obstacle.

But what article is on the page simply titled Bridge? In this case, Bridge redirects to the article Bridge; on Wikipedia, the default meaning of bridge is the structure. A hatnote on this default page points readers to the disambiguation page if they're looking for articles using a different meaning of the term. (Figure 8.3, "The hatnote on the Bridge article, pointing to the related disambiguation page" shows the hatnote that appears on the Bridge article.)

Figure 8.3. The hatnote on the Bridge article, pointing to the related disambiguation page The hatnote on the Bridge article, pointing to the related disambiguation page

Disambiguation pages can be created in more than one way, however. If no clear default meaning for a term exists, the main article may serve as the disambiguation page. For instance, if you go to Subway, you'll find that it is a disambiguation page leading to articles using these meanings for subway (among others):


 * Subway, underground railway, also known as a metro, underground, U-Bahn


 * Subway, an underground walkway, usually a tunnel

Descriptions on a disambiguation page do not need to be extensive. They do not serve as summaries of the articles they link to; they simply point to different possible meanings of a term and need only clarify the distinction between those meanings. Keep descriptions succinct: American film actor for an actor is probably sufficient; you don't need to include the films he has acted in. For pages that disambiguate between several people, include their profession, nationality, and birth and death dates (providing dates is especially important for an article on someone like George Williams, as half a dozen American politicians have that name).

Disambiguating Articles About People
Wikipedia has hundreds of thousands of biographies (approximately 20 percent of all articles). Because of this, special guidelines have been set up for disambiguating names. Wikipedia handles this complex area in a way that may initially appear unclear if you're creating or updating these types of pages. Note the templates used on pages and don't underestimate the issues involved with biographies.

Tidier Hatnotes
Hatnotes are small text messages at the top of an article. They are useful when only two articles might get confused and for directing readers to disambiguation pages. Wikipedia uses standard templates for hatnotes such as, , and. These templates add standardized messages to a page, which can be easier than writing out your own message (also perfectly acceptable). See Wikipedia:Hatnote (shortcut WP:HAT) for hatnote templates and common messages. The term hatnote is specific to Wikipedia and was created to avoid ambiguity because a headnote (the opposite of a footnote) is used in legal work.

Many complete proper names require disambiguation: John Smith, Thomas Adams, and Juan González are all examples of common names that need disambiguation pages to distinguish between individuals sharing that name. But Wikipedia also lists articles by surname alone. For example, Category:Irish surnames contains around 200 pages, each devoted to a single surname of Irish origin. If you go to Nolan, you'll find an extensive list of articles on Irish, British, American, Canadian, and other Nolans.

Thus, a surname page is very much like a disambiguation page: Nolan refers to numerous people. Sometimes these surname pages include (surname) in the title. For instance, Cooper is a basic disambiguation page, listing the many places called Cooper, a handful of well-known people named Cooper, and a pointer to the page Cooper (profession), which is about the profession of making barrels. Because Cooper is a very common English surname, Wikipedia also has a separate page Cooper (surname), listing articles about people with that name. This page exists in place of List of people with surname Cooper.

Two other kinds of pages about people exist: listings by given names and family history.

Given names are treated differently than surnames. If you search for John, you'll find this page in Category:Given names. Listing every article about a person with the first name John would not be useful. Instead you'll discover that Juan is the Spanish equivalent—in other words, the article is about the name itself. The basic page John is a disambiguation page that lists historical figures known just as John, such as the English King who signed Magna Carta. Use the template to classify these pages.

These topics are extremely popular on the Web. We mentioned in ../Chapter 1/, "What's in Wikipedia?" that Wikipedia believes that most family history is indiscriminate and only includes it when the family's history meets the standards of notability—and only in articles about specific families (not the general surname), such as Bancroft family, the owners of The Wall Street Journal until 2007. Family articles should be placed in Category:Families and its subcategories. That Bancroft article belongs in the categories Category:American families and Category:Business families.

Disambiguation Templates
Like other articles, disambiguation pages are tagged with templates that identify them as disambiguation pages and sort them into different categories. Here's how it all breaks down by template:


 * is the general disambiguation template. For example, Tom Thumb (disambiguation) lists articles about the folklore character, a railway locomotive, a feature film with Peter Sellers, a grocer in Dallas, Texas, and some Marvel Comics superheroes. In other words, miscellaneous lists are straightforward disambiguation pages.


 * is the template for human names. This template applies, for example, to Bill Gates (disambiguation), which lists not only Bill Gates of Microsoft but also "Swiftwater" Bill Gates, who took part in the Klondike gold rush, and various people more commonly known by the name William Gates.


 * is the surname page template. The Manual of Style for disambiguation pages (shortcut WP:MOSDAB, subsection Given names or surnames) describes how a surname page differs from a disambiguation page.


 * is the template for pages that disambiguate the names of places.

Redirects
Wikipedia:Redirect: The style guideline for creating redirects.

Help:Redirect: Help page on how to create redirects.

Disambiguation Pages
Wikipedia:Disambiguation: The guideline for creating disambiguation pages, with page naming conventions.

Wikipedia:Manual of Style/Disambiguation pages: The Manual of Style page with formatting guidelines for disambiguation pages.

Wikipedia:WikiProject Disambiguation: For cleaning up disambiguation pages.

Wikipedia:Hatnote: The hatnotes guideline.

Merge, Split, and Move
Working with and cleaning up individual articles includes determining if each article covers an appropriate scope and does not duplicate other articles. If two articles are very similar, you may need to merge them. On the other hand, if an article grows too long and unwieldy (or covers several topics), you may need to split it into more than one article. And if an article should appear under a more appropriate title, you need to move it. Moves and merges both create redirects from former page titles and copy content and revision history to a new page title.

Merging Articles
Wikipedia has no special process for ensuring that new articles don't duplicate old ones (this is why, in ../Chapter 6/, "Good Writing and Research", we suggest checking for other articles on the same topic before starting a new one). Editors who write new articles are responsible for making sure no duplicate articles (perhaps using a slightly different title) exist. If an editor doesn't check, however, and creates a duplicate article, other editors may eventually catch the duplication. In this case, they will most likely flag the two articles as candidates for a merge.

The goal of a merge is to end up with one good, coherent article that incorporates all facts, concepts, and references from both articles without duplicating material. The ideal merge results in a better article. No content should be lost in a merge; instead, all of the relevant facts should end up in one article, and the other, alternate title redirects readers to the new combined article.

Another, more complex case is when several small articles need to be consolidated into one more satisfactory and broader article. For instance, an article about a band member may be merged into the article about the band if little independent information about the musician in question is available. Sometimes a noun and antonym, or two similar terms, make more sense in a single article (e.g., Supralapsarianism and Infralapsarianism). These cases generally require more discussion and may be controversial.

A good merge is an unhurried, multipass procedure requiring many edits. Because merges require skill, a single editor often performs the merge once all the interested editors have agreed to it. This can vary from article to article; for articles where one title is misspelled or when the two articles are nearly identical, objections are unlikely. (William M. Ramsey and William Mitchell Ramsay is an example of this kind of duplication, where two articles were accidentally created about the same person.) Problems may arise, however, if you want to combine two similar concepts and another editor wants to maintain a distinction between the concepts. For instance, in mathematics, fractions and rational numbers are covered in separate articles—Fraction and Rational number—even though fractions are, in fact, usually rational numbers.

How to Merge Articles
Merging is a manual process that can be quite involved for longer articles. Assuming you want to perform the merge yourself, here are the steps to follow:

 Identify the articles you want to merge. Make sure they are, in fact, duplicate articles or otherwise need to be combined. Tag each of the articles to be merged with a special merge template. Insert the template at the beginning of the article:

where  is the title of the article that you want to merge with the article you're currently tagging, and the current month and year appears after  . Tag the other article to be merged, replacing  with the title of the first article. These templates alert readers and editors to the possible merge. (Figure 8.4, "The merge message template on the Bulgarian Education article, suggesting a merge to the article called Education in Bulgaria" shows this message at the top of the Bulgarian Education article.)

Figure 8.4. The merge message template on the Bulgarian Education article, suggesting a merge to the article called Education in Bulgaria The merge message template on the Bulgarian Education article, suggesting a merge to the article called Education in Bulgaria In any merge, one article will become the destination article (mergeto page), where all the content will be combined, and the other will become the redirected article (mergefrom page), which will become a redirect to the other article. If you already know which article should be which, you can use more specific templates:

on the redirected article

on the destination article

 The merge templates will place the articles into Category:Articles to be merged; adding the date means they will be sorted into a month-by-month category as well. Add a note to each article's talk page, describing why you think the articles should be merged if the reason is not apparent. After tagging the articles, wait a week (perhaps longer for obscure articles) for editors who have watchlisted the articles to comment on the merge. The idea is to leave sufficient time in case anyone disagrees with the merge. (If you get impatient in the meantime, you can find plenty of other merging work to do on older articles!) Review any comments left regarding the merge; if strong objections have been raised, don't merge the articles.</li> <li>If you have not yet decided, choose the destination article and the redirected article. If you aren't sure, discuss it with other editors on the relevant talk pages to resolve the matter.</li> <li>Edit both articles at once (use two browser windows or two browser tabs). First, copy the text from the mergefrom page to the mergeto page. Make sure to include all references, footnotes, external links, and see alsos (as for editing, you can draft the merged article first and save it later, or you can use subsequent edits to clean up your work). Add an appropriate edit summary when you save the article indicating where the content came from, such as "merging content," and include the title of the article you're merging from.</li> <li>Use several edits to work on the logical order of the new, combined page. Determine the extent of duplication, which sections need to be cut or moved, and if any new sections need to be started. Reducing the duplication in stages is best; sort the material by combining duplicate sections. It is best to determine duplication section by section rather than when you first combine the articles.</li> <li>Polish the text of the new article and work on readability. Try not to delete content, but focus on creating a quality article. Don't lose references and footnotes, and cite any questionable statements.</li> <li>Replace the text on the mergefrom article with a redirect to the new destination (mergeto) article. Save the page, indicating which pages are being merged in the edit summaries.</li> <li>If the two articles disagreed about a fact, include this information in a note on the talk page of the destination article. Also indicate any other changes, such as text cuts or deleted images.</li> <li>Check What Links Here from the redirected article to find double redirects that may have been created by the merge; fix these redirects by editing them to point to the destination article.</li> <li>When you're finished, remove the merge tag from the destination article, and add a note indicating that the merge is complete to your original threads on the talk pages.</li> <li>Congratulate yourself on completing the merge!</li> </ol>

For major consolidations with more than one article, you can use the template. Proceed with the merge one article at a time; you will still need to determine a destination article.

Splitting Articles
An article should be split into multiple articles when it has become unwieldy to read and edit. An article should also split into multiple articles if it deals with several diverse topics better suited to individual articles. An article should not be split, however, if the resulting articles would be small stubs. For example, an article about an author should not be split into small articles about each of his or her books; in this case, one long article about the author and his or her work with redirects from the book titles is usually best.

Very long articles are undesirable for a variety of reasons: They are difficult to navigate and read, and in some older browsers and mobile browsers, you can't edit pages with more than 32KB of text. Long articles can also take a long time to load on slow Internet connections. The Manual of Style deals with these points at Wikipedia:Article size (shortcut WP:SIZE).

When a long article includes too much detail on a narrow subtopic, you might want to split it. Splitting is an important aspect of Wikipedia:Summary style, which was mentioned in ../Chapter 6/, "Good Writing and Research". Long articles should generally follow summary style. Each section of the article should summarize the major topic points with links to specialized articles that fill in detail. For example, an article about a sports team should not be dominated by material on a famous coach: The coach should be discussed in a separate article and the material sensibly divided between the team's article (which would cover the coach's work with the team) and the coach's article (which would cover mostly biographical information).

Procedurally, a split is similar to a merge. First, post the template on the page, perhaps at the beginning of the section you propose splitting into its own article. Add a note to the article's talk page before doing anything drastic. You should normally wait for any comments and discussion among editors.

If a section of text needs to be split into its own article:


 * 1) Give the new article an appropriate title.
 * 2) Edit the old article to obtain the wikitext for cutting and pasting, so any formatting is preserved.
 * 3) Add an appropriate edit summary, indicating that you're splitting the old article and giving the names of the two articles using wikilinks, for instance, " Split History of Alaska out from Alaska ".
 * 4) Add a summary to the old article where you cut the text rather than leaving a gap, and add a wikilink to the new article.

Using the History of Alaska example, in the main Alaska article just add one or two short paragraphs summarizing the high points of Alaskan history. At the top of the section called ==History of Alaska==, include a link to the new, more specialized article, along with a message such as " Main article: History of Alaska ". This message tells readers to click the link to go to that article if they want more information on Alaskan history. Use the template to produce a neat message:

Moving Pages
If an article is located at the wrong title, you can move it to a new title as long as another article isn't already located at that title. Moving is the only way to rename a page.

Moving a page is simple but has several implications. To move a page, you must be logged in and have an account that is more than four days old (as of early 2008). Click the Move tab at the top of the page you want to rename. In the form that appears, type the new title that you want the article to have and the reason you are moving the article to the new title. Keep the Move associated talk page box checked. Check the Watch this page box to add it to your personal watchlist.

A typical move may be as minor as moving PT Barnum to P. T. Barnum, (adding periods and a space between the initials). Page moves are routinely used to fix title style (correcting punctuation, including the type of apostrophe, or using a hyphen for an en dash are common fixes).

Page moves accomplish three important things:
 * 1) Change the article title
 * 2) Move the page history to the new page title
 * 3) Create a redirect from the old title to the new title

They may also result in three other things:
 * 1) Turn redirects to the old title into double redirects
 * 2) Fill in redlinks, if the new title has been linked to on other pages
 * 3) Prevent future duplication

Creating double redirects is negative, but the other two are positive. If, for example, you move an orphan article with a poorly chosen title to a more reasonable title, you may be rewarded with a stack of new backlinks to the page if others have already linked to that new page title elsewhere. Broken links have suddenly become bluelinks thanks to your observant work.

Limits on Moving Pages
If you're trying to move an article and another article already has the title you've chosen, you won't be able to move your article there. Examine both articles: Should they be merged instead? See "When a Page Move Is Blocked" in Section 4, "Housekeeping" for what to do in that more complicated scenario.

The only time you can move an article on top of an existing page is when that page is a redirect with minimal history.

The move function is the only acceptable way to retitle an article, as moving transfers the version history along with the article itself. Although you can easily copy and paste article content into a new page and then redirect the old page to the new one, doing so is wrong. This results in an article with no history of previous versions, creating a confusing record. These so-called cut-and-paste moves can be fixed by an administrator through the history merge process; see How to fix cut and paste moves. When merging or splitting an article, always provide a good edit summary detailing where the content came from.

Fixing Double Redirects
After you move an article, you're responsible for removing double redirects by checking What Links Here for the old article. After you've moved an article successfully, a message reminds you to check for double redirects and gives you the correct text to use. A good editor will not neglect this task, even though bots on the site may get to it within a few days.

Undoing a Move
Page moves can be undone. Immediately after moving an article, you will have the option to revert back if you realize you've made a mistake. Undoing is possible only if the article from which the original move was made has not subsequently been edited. If it has, you can reverse the move function by going back to the original title. If that is not possible, you will need an administrator's help. See How to rename (move) a page.

Contentious Title Changes
After you've worked on Wikipedia for a while, you'll get a feel for what is considered contentious and what is not. For article titles, the basic rule is to use the most common expression. Titles should not be changed to make a point—political or otherwise. Obviously, if the new title fails to describe the article's text in a neutral way, problems may arise. In case of doubt, discuss the new title on the article's talk page before moving the article.

For example, consider what type of article might justify including the word massacre in its title: frequent discussions about this type of issue have occurred, and nationalist opinions become involved. For example, the use of the word massacre has been contentious in relation to Deir Yassin massacre, which some have wanted renamed Battle of Deir Yassin. In this instance, Wikipedia engages with contentious history, and sharp debates cannot be avoided.

Wikipedia prefers to be correct rather than populist regarding some exceptions to using the common name or title, such as articles about aristocrats. But take, for example, the article J. D. Salinger. Moving it to Jerome David Salinger would cause annoyance because J.D. Salinger is never referred to by his full name. Although full names are often better than initials, in this instance, they aren't; Salinger's initials serve as a sort of pen name. (More examples of this can be found at List of people known by initials.)

Merging Articles
Wikipedia:Help:Merging and moving pages: Help merging and moving pages

Wikipedia:Merging: More information about merging pages

Wikipedia:Category:Articles to be merged: Articles to be merged, sorted by the month they were tagged

Splitting Articles
Wikipedia:Summary style: The section of the Manual of Style that deals with splitting articles

Wikipedia:Category:Articles to be split: The category of articles that need to be split

Wikipedia:Article size: About article size

Moving Pages
Wikipedia:Moving a page How to move a page

Categorize
Each page in the Category namespace represents, lists, and perhaps defines a category, or grouping of related pages. Categories place pages on related topics in one "container." A category page on Wikipedia should offer an overview of the coverage of a particular subject. How extensive is the coverage? How are articles organized? Is the particular topic you want there, but under a title that wouldn't be your first choice? Is there a subcategory that's a better fit for the area you want to research?

You learned how to navigate with categories in "Browsing by Categories" on Section 3.4, "Browsing by Categories"; in this section, you'll learn how to use them as an editorial tool.

All articles should be in at least one category; most articles are in more than one category. Some areas are particularly important to categorize: For instance, work is ongoing to track all Wikipedia's biographies of living persons in Living people, with the number of articles running well into the six figures.

When an article is in one or more categories, this information appears at the very bottom of the article in an automatically generated section called Categories.

You Can Change Your Skin
Different skins—the formatting for how the site looks, which can be changed in your preferences (see ../Chapter 11/, "Becoming a Wikipedian")—display categories in different locations. If you refer constantly to categories on articles, changing your skin to classic, which displays categories at the top rather than at the bottom of the page, will save you from having to scroll down to use them. Go to My Preferences in the upper right-hand corner of the page if you're logged in. To change back, go to Preferences at the top right in the classic skin and select Monobook (the default skin).

Clicking any category link will take you to the main page for that category. As described in ../Chapter 3/, "Finding Wikipedia's Content" (see Figure 3.10, "Example of a category page (the category of Fictional Countries), showing editable sections" in Section 4.4.1, "Structure of a Category Page"), a category page has four parts:
 * 1) The explanation of the category; this text (along with the category's discussion page) is editable and is what you'll see if you click Edit This Page.
 * 2) A list of any subcategories within the category; these are listed alphabetically, but if the category is very large, the list may be spread over several pages.
 * 3) A list of links to articles in the category; this list is automatically populated. If the category is very large, the listing may be spread over several pages; only the first 200 links will appear on the first page. Click Next 200 at the bottom of the page to see the next page of entries.
 * 4) At the very bottom, you'll find a list of the categories that the category you're viewing is part of. These are editable by editing the category page.

Lists vs. Categories
The debate over whether categories or lists should be used to sort articles continues on Wikipedia. Because categories are automated, they are somewhat inflexible, compared to lists that are created as editable articles. The ability to edit means lists can be annotated and referenced, which is the main reason lists persist on the site.

Categorizing Basics
You can assign a page to any category simply by adding

to the page's wikitext. Substitute the actual name of the category in place of categoryname.

For example, to add the article Bozo the Clown to the Clowns category, you would edit the article and add the text  at the very bottom of the page.

Placing an article in a category by adding a category tag does two things:
 * 1) It automatically lists the article on the appropriate category page.
 * 2) It also provides a link to that category page in the list of categories at the bottom of the article.

Though no connection exists between the location of the category tag in the article source text and where the Categories box appears on the page, the general convention is to place categories together at the end of the source text (though before any interwiki links), one per line, so they don't affect the rest of the text and are all in one place. (Figure 8.5, "Article wikitext with multiple categories listed near the end of a page (after templates and before interwiki links), from the article Exploding whale" shows the placement of categories in an article's wikitext.) Wikipedia has no standard order for categories.

Figure 8.5. Article wikitext with multiple categories listed near the end of a page (after templates and before interwiki links), from the article Exploding whale

Articles can be included in more than one category by adding multiple category tags. For example, for a person no longer alive, the standard categories are year of birth, year of death, and occupation. Most articles are naturally in more than one category.

Most Categories
The page in the greatest number of categories can be found at the special page Special:Mostcategories. As of March 2008, a large number of Fauna categories were added to Red Fox, giving it 96; second as we go to print is Black Rat. Prior to this, the article in the greatest number of categories was Winston Churchill, with 67; these include Category:Knights of the Elephant, for holders of a Danish decoration, and Category:Nobel laureates in Literature, from 1953, as well as Category:Old Harrovians and Category:Members of the Queen's Privy Council for Canada.

To link to a category in wikitext without categorizing the page, type

Category:Instruction

Doing this is useful for "See also" sections in articles. This is also vital if you want to discuss a category on a talk page. If you leave out the first colon, the text of the link won't be displayed, and the page will be categorized in that category.

Categories and Content Policy
Like everything else on Wikipedia, categories are not canonical. Sometimes they are even incorrect or misleading, usually as the result of an honest mistake. Articles should be placed in categories simply to inform, never to make a point or forward a controversial position. Obviously, if an article about a person is in a category damaging to his or her reputation, the classification should be fully supported within the article. No one should just add Category:Murderers, unjustified, to a biography. Wikipedia doesn't allow its category system to be used as a way of commenting on content.

In general, anybody adding categories to an article should follow the same basic policies of Verifiability, No Original Research, and Neutral Point of View that govern the rest of Wikipedia. Categories are part of the informational content of an article and should be treated appropriately: They should be supported by references (or more properly by statements in the article's text that are themselves referenced), especially if the category is contentious. (One disadvantage of categories as opposed to lists: You can add sources to a list to support inclusion, but you can't annotate an article's categories directly.)

Wikipedia has many guidelines for categorizing articles; Wikipedia:Categorization FAQ is one place to find them. Wikipedia:Categorization of people, another guideline, explains the sensitive subject of placing people in categories that might affect their reputation. Especially for biographical articles about living people, use caution when adding categories other than very formal and descriptive ones.

Creating New Categories
You can start a new category easily. If you add a category to an article, but the category doesn't exist yet, it displays as a redlink in the article's list of categories. To turn the redlink blue, simply click it (or visit Category:New category name where new category name is the category you want to create) and add some content, such as a brief description of the category and the categories it is a subcategory of, to the category page. Any pages that you or others have already tagged with your new category name will automatically be listed on the new category page.

For example, Category:Poisoned apples could be created by adding this text to the new page Poisoned apples:

A poisoned apple is an apple that has been poisoned.

The description will appear at the top of the category page, and adding the categories will instantly make poisoned apples a new subcategory of the Apples and Fairytale Objects categories.

All new categories should have their broader categories listed, but including a description is optional; in this case, the description isn't very helpful. In some cases, though, a good description (perhaps linking to the main article on the subject) will help the average reader, especially for obscure subjects.

Wikipedia also has naming and structural conventions for creating categories. Use plurals, for example Category:Pigs, for categories. This convention differs from the article title convention of generally preferring the singular form. Proper names such as Category:Vermont, which collects articles about the state, or collective headings such as Category:Greek mythology are also common category names.

Before creating a new category, make sure the category you want doesn't already exist under a variant name (check articles similar to the one you're trying to categorize). Creating categories that are not obviously needed is considered a nuisance.

Subcategories
Categories can have subcategories. Anyone can create or alter subcategories by simply categorizing the category page. For instance, you could make Category:Piglets a subcategory of Category:Pigs; simply tag the Category:Piglets page with. Using the subcategory and supercategory structure is a good way to browse the site and is discussed extensively in ../Chapter 3/, "Finding Wikipedia's Content".

Here, we'll discuss the issues around classifying articles using detailed categories. Are detailed subsubcategories a good thing or not? Certainly having categories that contain too many articles can be unwieldy; a category with more than 200 articles in it requires multiple pages. Subcategorizing the articles into more distinct categories can help keep categories manageable.

Subcategories are useful on Wikipedia to subclassify when the schematic being followed is fairly natural to the subject matter and the relevance is evident. Category:Politicians with blue eyes is not helpful—why would anyone be looking for this information? But Category:Canadian buskers is an acceptable subcategory of Category:Buskers or of Category:Canadian musicians. Subcategories should offer the general reader a convenient way to navigate a category and also provide information about the material included in a category.

Following a general but not quite universal convention, articles should not appear in both a category and a subcategory. For instance, Category:Beetles within Category:Insects classifies some insects more precisely. According to the convention, the beetle articles should not also be in the more general Category:Insects. Therefore, in searching Category:Insects for all the Wikipedia articles on insects, you would also have to search Category:Beetles and, within that, more than a dozen subcategories to find all of the beetle pages. Going through all the subcategories is the only comprehensive way to find all the articles related to a larger category, such as insects; if in this case you went to the page List of insects, you'd discover this list is a redirect to Category:Insects. While finding all Wikipedia articles about insects is probably unreasonable (as the category is enormous), creating extremely detailed subcategories for smaller topics can make it difficult to see all the related articles at a glance. On the other hand, articles should always placed in the most detailed category that applies: An article about a beetle found in New Zealand should be placed in the Beetles of New Zealand category, not the higher-level category Beetles.

Exploring a Category and Its Subcategories
Wikipedia has a way to show an extended view of the whole structure of a complex category. The special page Special:CategoryTree will show you all of a category's subcategories arranged in a clickable tree structure. Go to the page and type the name of the category you want to examine in the box provided (JavaScript must be enabled in your browser). This tool makes it easy to see related articles in different subcategories. You can also include an expandable category tree on a wiki page by using the tag. No brackets are needed around the name of the category with this tag.

Categorization Projects
You can find lots of information about projects to improve the use of categories at Wikipedia:WikiProject Categories/Current subprojects. You can also find an overview at Category:Wikipedia categorization.

One long-standing categorization project that crosses all disciplines is Wikipedia:WikiProject Stub sorting. This project maintains the article categories for stubs, a list of which can be found at Wikipedia:WikiProject Stub sorting/List of stubs. These special categories are applied to articles not with standard category tags but with templates, which are discussed in the next chapter.

Housekeeping
Now that you've seen how the six tools can be used for hypertext editing, we will discuss a few problems that can arise when you try to apply the tools discussed in this chapter and solutions to those problems.

When a Page Move Is Blocked
Suppose you want to move article P to title Q, but the MediaWiki software blocks the move. P and Q might be articles on identical topics; then you will need to merge the articles.

If the other article Q is on a different topic than P but uses the same title that you wanted to use for P, then you need to create a disambiguation page for the main term and move the other articles to appropriate titles, which will then be linked to on the new disambiguation page. For instance, you might want to move Jolly Green Giant to Green Giant—but you'd find that Green Giant is already taken up with a page about the company. You could move the page Green Giant to Green Giant (company), and Jolly Green Giant to Green Giant (symbol). Then you could go back to the page Green Giant—it will be a redirect to Green Giant (company) from the move—and edit it to be a disambiguation page pointing to the two articles. Any other articles about green giants could also be listed. The page Jolly Green Giant will be automatically turned into a redirect to Green Giant (symbol), but you'll need to check for double redirects and add hatnotes to the two articles pointing back to the disambiguation page. This series of actions will help this small corner of Wikipedia make more sense to the reader.

Sometimes the situation is more complicated. Page moves to temporary dummy titles can help. You can tag any unneeded redirects you create for speedy deletion when you're done. See Help:Moving a page for more guidance and Requested moves to request administrator help with moving a page.

Default Meanings
Sometimes an article about a lesser character, say from an anime or comic, will be created before the article about a more important figure with the same name. A disambiguation page should be created in this case. For the good of the encyclopedia, the lesser character shouldn't become the default meaning, however. For example Thor, the Norse god, must have priority over Thor (Marvel Comics). Problems of this type have to be sorted out by someone who understands blocked page moves.

Moves are best made from a more general title to a more particular title: from John Jones to John James Jones, for example. That leaves the way open to making John Jones a disambiguation page. Moving uphill, or removing information from a title, is sometimes more problematic. Removing information can often make a title ambiguous, for example, moving George W. Bush to George Bush. If you remove information from a title, you risk deciding on the Wikipedia default meaning: You may be telling the world that John Jones should be read as John James Jones.

In other words, make titles more informative and specialized to the topic. But don't add titles like Dr., honorifics, or post-nominal letters like initials after names; this is against Wikipedia conventions. Moving articles to more general titles should be used mainly for verbose titles, like moving List of Japanese Government and Private institutions and Groups (from 1930s to 1945) to List of Japanese institutions (1930–1945).

Avoiding Disambiguation Pages
Wikilinks in articles should generally point to the exact article title meant, not a disambiguation page, since a link with a variety of possible meanings can be confusing to a reader unfamiliar with a topic. The process of changing wikilinks to point to precise articles instead of disambiguation pages is called avoid disambiguation pages. Generally, this work is done by checking What Links Here for disambiguation pages.

Here's an example from the article Rectangle. The initial text in the article was

A square is a special kind of rectangle where all four sides have equal length;

But Square is a disambiguation page, which includes the meaning Square (slang) for an un-hip person. To avoid the dab page, change the link to Square to the following:

A square is a special kind of rectangle where all four sides have equal length;

The text now reads the same as before, but the destination of the wikilink is precise and correct. If an article using the precise meaning of a term hasn't been created yet, use a red-and-piped link rather than linking to the disambiguation page (which would be confusing). The redlink may also prompt someone to create the new article.

Finding Disambiguation Work
To find lists of disambiguation pages, including the disambiguation pages that need to be improved, try browsing through CategoryDisambiguation]]; the subcategories at the top sort disambiguation pages by topic. If you want to work on disambiguation pages that need cleanup help, consider joining the disambiguation WikiProject: WikiProject Disambiguation. See Disambiguation pages with links (shortcut WP:DPL) for a list of disambiguation pages that have incoming links (which should instead be links to more precise articles).

Controlling Category Sorting
Pages within categories are displayed alphabetically by the first word of the page title, but this order can be modified by sort keys.

Category:Presidents of France may look quite ordinary (Figure 8.6, "Category:Presidents of France"), but a few things are going on here. Under the letter G, you'll find the article for Charles de Gaulle. Under N, you'll find the article on Napoleon III of France, but under S (not N), you'll find the article on Nicolas Sarkozy. The case of Sarkozy obviously fits sorting by surname, but what else is happening here? Napoleon III was a president before he was an emperor, but his surname was, of course, Bonaparte. De Gaulle is a surname, but using the appropriate convention for French names, the de is not considered here.

Figure 8.6. Category:Presidents of France

In a category, you would generally expect the article John Smith to be sorted under S for Smith rather than J for John. Wikipedia has two ways to achieve this result: magic words and sort keys. These two approaches have the same effect—making category listings treat the John Smith page article as if its title were Smith John—but magic words affect every category a page is in, while sort keys only work one category at a time. Each is highly flexible.

The magic word for default sort is used like a template:

For the page John Smith, it would be filled in like this:

and placed in the wikitext above the list of categories. To classify Charles de Gaulle under G, the template would be filled in this way:

The use of this template affects every category page that Charles de Gaulle might be placed in (potentially dozens); the article will always show up sorted under G.

To only sort an article in a single category, or to vary sorting according to the category, use a sort key, which is added after a pipe character placed in the Category link in the article text:

If you want to list Napoleon III under B for Bonaparte, for this particular category, enter

on the page Napoleon III of France; that will affect just how the article is sorted in the category Presidents of France. See Wikipedia:Categorization#Pipe tricks and sort keys for more examples and explanations.

Although titles usually consist of plain text, they may begin with other symbols. The ordering used for category sorting when extended to non-alphanumeric characters is ASCII order, a standard used in byte codes for computing. Article titles beginning with numbers come before article titles starting with the letter A and article titles starting with symbols are always displayed before these, using a particular order for symbols. The article (Like) Linus, beginning with an opening parenthesis and about a demo by The Deftones, would precede the article about @Home Network, a defunct ISP, beginning with @, if these two articles were ever placed in the same (unlikely) category.

The use of ASCII order explains one more thing about the Presidents of France category page. The listing starts with President of the French Republic, under an asterisk (*). This is because in the article President of the French Republic, the category tag reads

The asterisk is a device for bringing the article to the top of the listing so it is much more prominent. This method is commonly used for highlighting the main article in a category—the article that will give the reader an overview of the whole topic. A blank space after the pipe character is an extra refinement and has the same effect except no asterisk is included on the category page.

Categories and Templates for Redirects
Certain links on a category page may appear in italics. This is because these are links for redirect pages. If you click the link, you go to the page to which the redirect leads (not to the article with the title you expected).

The probable explanation is this: The redirect is anchored to a section of an article, and the category is right for that section but would be odd for the whole article. For example, the article might be about an author and the section about a film made from one of the author's books: Placing the author's name in a film category wouldn't be correct.

Another example of how to use this device is illustrated by the French Presidents example. Charles Louis-Napoléon Bonaparte is a redirect to Napoleon III of France. The category tag  could be included in the redirect, so the category page would include the correct name for his time as president and be sorted under Bonaparte.

Templates on redirects are mostly used to flag redirects that could usefully become articles in their own right. See Category:Redirect templates.

Process-Style Resolutions
Your problem may have a resolution, if you only knew where to go to get an answer.

Category deletion
Annoying and useless categories and categories that need to be renamed (often required to apply conventions consistently) are handled via a process. Go to Wikipedia:Categories for discussion (shortcut WP:CFD) to apply for deletion, merging, and renaming of categories or to participate in discussions about those issues. The process takes about a week.

Problem redirects
Go to Wikipedia:Redirects for discussion (shortcut WP:RFD).

Disagreement about default meanings
Editors are supposed to discuss difficulties about default meanings and come to a resolution. Failing that, Wikipedia:Requested moves (shortcut WP:RM) is the place to discuss any contested title change.

Merges without consensus
Most mergers should be simply tagged and discussed on their respective talk pages, but proposed merges can also be listed on Wikipedia:Proposed mergers for wider discussion. If there is no consensus, the merge should usually not occur.

Contested title changes
Go to Wikipedia:Requested moves (shortcut WP:RM) to discuss moves when consensus is not clear. This page is where matters concerning moves can be sorted out if there is real disagreement. Just add the request along with a short justification, and refer back to this page for a few days. Any editor may comment.

Fixing cut-and-paste moves
Go to Wikipedia:Cut and paste move repair holding pen (shortcut WP:SPLICE) if you need page histories fixed after copy-and-paste moves.

Summary
Improving Wikipedia can go beyond editing text. The techniques discussed in this chapter complement the more glamorous business of writing articles. They allow you to present the site's content to the readers more clearly by creating navigational structures and sorting existing content.

There are two special types of pages—redirect and disambiguation pages—that are used to help readers navigate Wikipedia. Redirects are a special type of page that take readers from one page title to another when more than one possible title for an article exists. Wikipedia has millions of redirects, all helping readers navigate and search the site. Disambiguation pages, on the other hand, pull together a list of articles with similar titles that could be confused. These pages can be created for any term with multiple meanings, as well as for common personal and family names that may refer to more than one person or family.

Part of editing articles is ensuring that each article's scope is appropriate. If Wikipedia has two or more articles about the same topic or with very similar content, these articles may need to be merged. Any editor can merge two articles by editing them and combining their text on one of the pages and then redirecting the other article to the new combined article. If an article gets too long and unwieldy or deals with multiple disparate topics, the article may need to be split into two or more separate articles. Any editor can do this by creating a new page and copying some of the old article's content to the new page. Finally, an article may be created using the wrong title or a later decision is made to rename an article. In this case, that article needs to be moved to a new title.

Finally, categorizing articles in appropriate categories is a fundamental part of sorting Wikipedia content, making it more accessible to readers and editors. Anyone can help with categorizing pages. Anyone can also create new categories, but understanding how the process works ensures your work is consistent with existing schemes.

For all of these editing techniques, Wikipedia has developed many guidelines detailing how they are done and has created several community processes for dealing with problem cases.