Disambiguation in Wikipedia is the process of resolving the conflict that occurs when articles about two or more different topics have the same natural title.
Wikipedia thrives on the fact that making links is simple and automatic: as you're typing in an edit window, put brackets around Mercury (like this: [[Mercury]]) and you'll have a link. But were you intending to link to Mercury the element, the planet, the car, the record label or the Roman god?
Solving this ambiguity can be done in several ways:
Disambiguation involves three steps:
|Fixing links to disambiguated topics|
A warning, though: people have a tendency to create disambiguation pages without fixing all the links to them. The result is that Wikipedia is left in a worse state than it was before the page was split.
Before creating a disambiguation page, click on "What links here" to find all the pages that link to the page you are about to change. Make sure those pages are fixed or that they won't be adversely affected before you do the split.
A code of honor for creating disambiguation pages is to fix the mis-directed links that will be created when the disambiguation page is made.
For creating the specific topic pages, a few options are available. If there's an alternate name or more complete name that is equally clear, that can be used. For example, Java programming language, Titan rocket. Otherwise, a disambiguating word or phrase can be added in parentheses. The word or phrase in parentheses should be one of two things: a generic noun describing what the specific title is an instance of (for example, Mercury (element), Seal (mammal)); or the subject or context to which the term applies (for example, Union (set theory), Inflation (economics)). Rarely, an adjective describing the title can be used, but in this case it's usually better to rephrase the title to avoid parentheses. If there's a choice between using a short phrase and word with context (for example, "Mathematical analysis" vs. "Analysis (mathematics)", there is no hard rule about which is preferred, and one can often create both, one redirecting to the other.
A special case of using a "context" to disambiguate is when the context is a book or other creative work, such as with articles about fictional characters. For example Dagny Taggart (Atlas Shrugged)[?]. If there is a choice between disambiguating with a generic term or with a context, choose whichever is simpler. For example "mythology" rather than "mythological figure". Use the same disambiguating phrase for topics within the same context.
To conform to our normal naming conventions, the phrase in parentheses should be treated just as any other word in a title: normally lowercase, unless it is a proper noun that always appears capitalized even in running text (such as a book title).
For more on which word or phrase to insert in the parentheses, see Wikipedia:Naming conventions and Wikipedia talk:Naming conventions.
|The disambiguation page|
There is some flexibility in creating the disambiguation page itself, or even whether it is necessary to create one at all. As mentioned earlier, if the title clearly has one central most important meaning, and one or two lesser-known meanings in narrow contexts, it is probably better to have the full article about the primary meaning under the simple title, after brief links to the special uses.
For example, the poker article covers the card game; it is unlikely that there will ever be an encyclopedia article on fireplace pokers, but if we did create one, then we could link to it from the existing poker article without having to move that article to "Poker (game)".
If a disambiguation page is merited, it can be as simple as a bullet list of specific articles with links and perhaps a brief one-line description of each (saving details for the specific articles), or it might have some explanatory text of its own if differences need to be explained, or if there is interesting history of the term itself independent of the specific topics. If each of the topics themselves only has a sentence or two, it may be simpler just to put all of them together in one article.
Which method is appropriate will depend on the nature of the subject. The articles below serve as examples of what can be done (and a few examples of what shouldn't be done, but hopefully not many). Note that a disambiguating page may look a lot like a dictionary entry. We try to maintain a policy that Wikipedia is not a dictionary, so resist the urge to make such pages even more dictionary-like than they already are (for example, there's no need to put etymologies or pronunciations, unless those serve to clarify the topics).
You may want to include a note such as the following (which you can copy and paste) at the bottom the page:
Some people don't understand what such a notice accomplishes, however, and recommend against them. Others recommend a shorter version:
|Links to disambiguation pages|
There is rarely any need for links directly to disambiguation pages--in most cases links should point to the article that deals with the specific meaning intended, and not to a disambiguation page. Before making a page into a disambiguation page one should first look at each page that links to it (using the "pages that link here" feature of the software) and correct the links as appropriate. Of course, the whole point of making a disambiguation page is so that accidental links made to it will make sense, so it's not a major problem if there are still links to it--indeed some may argue that finding unexpected things is part of what makes Wikipedia interesting (as long as you can still find the expected things as well).
The Wikipedia software has a feature that lists "orphan" pages; that is, pages that no other page links to. But for disambiguating pages, that's perfectly correct: we usually want pages to link to the more specific pages.
So, in order to make the orphans list more useful by not cluttering it with intentional orphans, disambiguation pages are linked from either