|This page in a nutshell: Wikipedia has no formal process for deciding what content is acceptable but, in any given situation, the three most important factors are: what the relevant content guidelines say, what publicly available sources confirm, and what is the general consensus of Wikipedia editors who choose to get involved.|
New Wikipedia editors often have a difficult time understanding how decisions are made to determine what material is allowed or not. As previous readers of Wikipedia, they are already aware that the site's content can be exceptional, but also very poor. Its rules are sometimes crystal clear, and other times seemingly incomplete. Resolving these apparent contradictions and understanding the uncoordinated, emergent model of creation, revision, and exclusion of content on Wikipedia is the focus of this essay.
Among the first things new contributors have likely learned is that Wikipedia is an open collaborative project maintained by a community of volunteers who write and organize the encyclopedia according to a great many rules about appropriate content and editor behavior. But synthesizing this into a big picture version of how Wikipedia actually works can be very confusing, especially when there is so much inconsistency across the project. To understand better how any specific content one wishes to add to (or change, or remove from) Wikipedia will be received, think about it in terms of these three questions:
This essay describes what you need to understand about answering these questions. It cannot answer these questions for you, nor can it address every possible circumstance, but it will put you in the right frame of mind to find the correct answers.
Wikipedia's basic philosophy can be found in a short page called the five pillars, and it's a must-read for orienting yourself to Wikipedia's style of thinking. These principles inform the two main types of rules that Wikipedia editors have written for themselves: policies and guidelines. Policies must be followed closely, and failure to do so risks restriction from editing. Guidelines should almost always be followed, and failure to do so risks censure. Both types of rules cover the content of articles as well as the behavior of contributors. There is also a third type of rule which is not strictly enforceable: essays. Technically, these are the opinions only of the editors who write them, but some carry the equivalent weight of a guideline if they are widely accepted.
You should also be aware of Wikipedia's three core content policies. They include writing from a neutral point of view, writing only about information that is publicly verifiable, and permitting no original research to be included in Wikipedia articles. But that still leaves many questions about what a Wikipedia page should look like, so there is both a page with prescriptive advice about writing better articles and a long list of proscriptive advice about what Wikipedia is not supposed to include.
A key guideline which often comes up for those just getting started is one about when you want to write a new article that doesn't exist. This is called notability, and it is a fairly dense explanation of an ambiguous concept that tries to answer a difficult question: which topics are suitable for a Wikipedia entry? The simplest possible answer is: a lot of in-depth coverage from well-regarded news sources demonstrating public interest in the topic. Because this is so complicated, there are separate pages explaining how it relates to, among other things, companies and organizations as well as people. It's hard not to see this as a measure of "importance", especially considering the guideline is called Notability. But you should try: Wikipedia cannot cover all kinds of things that are important within their own field, but do not meet Wikipedia's specific requirements. These topics may be worth including in another directory or database, such as Wikidata, which has a much lower threshold for inclusion.
Determining what content is allowed in articles is more complex still. A good place to start is a section of the neutral point of view policy about due and undue weight, meaning how to regard the proportionality of specific information in relation to the larger topic. Also relevant is the essay about including criticism in Wikipedia articles, which you may be surprised to learn specifically recommends against including "controversy" sections in most circumstances.
The specific style of writing content for Wikipedia is governed by the site's manual of style, which itself has a multitude of sub-pages governing everything from the correct way to title articles to Wikipedia's preference for gender-neutral language to explaining when you should capitalize the word "The".
The verifiability guideline requires that anything you want to add to Wikipedia needs to be publicly available information, which usually means bringing a citation to back up your claims. But it's not nearly so simple: Wikipedia requires these sources to meet a certain threshold for integrity, hence a very important guideline about identifying reliable sources, described below.
Like the question of notability, there is no clear line separating the acceptable from unacceptable. For most non-historical and non-scientific topics, well-respected news organizations writing for a general audience are best, provided the cited source is written by a full-time employee, and not an op-ed or an interview where the interviewee is not presumed to be fact-checked. Peer-reviewed academic journals are even better, but harder to come by. Most anything else is of very limited use: press releases, industry analyst reports, unpaid contributor blogs even at big publications (Forbes contributor posts, for example) are not accepted. Social media accounts are right out. For more information about how Wikipedia thinks about these things, there's a useful essay that explains how Wikipedia evaluates independent sources.
You might be surprised to learn that government reports, hearing testimony, 10-K filings of public companies, and other documents created through bureaucratic processes are best avoided. But they're reliable, right? Likely so, but the question Wikipedia editors will ask is: which specific details from this report are worthy of mention? Wikipedia effectively outsources these judgment calls to journalists and experts (who aren't connected to the subject) published in reliable sources. The underlying principles are covered in the policy about original research and depend on the concepts of primary and secondary sources: the government report is a primary source, and the publication whose editorial staff contextualizes it is the secondary source. Wikipedia strongly prefers secondary sources. (There are also tertiary sources, including textbooks and encyclopedias—like Wikipedia—but for most topics, these are much less common.)
An all-too common mistake in writing new content for Wikipedia is to begin with what you want to say, and then to go looking for sources that confirm the details. Very often, you won't find they say exactly what you want. Or, if you try to combine two articles to imply something neither quite comes right out and says, you'll run into the admonition against synthesis of published material. The source must say it clearly, or you can't.
The best thing to do is to begin from research, and write about only what you find in reliable sources. Use Google, Google News, Lexis-Nexis, HighBeam, or any such news archive or database to which you have access. Copy everything to a text document, highlight the relevant parts, organize the salient details, and rewrite it in your own words, in an even-handed manner, free of opinion and jargon. Also, learn how to use citation templates. You may not get every detail you want, but you'll be a lot closer to success than starting from your idealized version.
But what if you find that a supposedly reliable source is wrong? Alas, this isn't as rare as it should be. While Wikipedia's editors are well aware that even reliable sources get things wrong, their assumption is that a news publication's intellectual independence means it's usually trustworthy. In most cases, if the sources are wrong, and if you can't find another reliable source that gets it right, you will probably have to live with it. If in doubt, leave it out. For more about this widely-acknowledged conundrum, look to a somewhat controversial essay about how Wikipedia favors verifiability, not truth. And know this: you're not alone in finding this a point of frustration. Wikipedia editors want to get it right—but they still have to play the odds.
At long last, we arrive at a major topic not yet discussed: conflict of interest. It's a familiar term, and on Wikipedia it nearly always refers to the question of whether a contributor has a financial motivation for editing an article or proposing a change: on behalf of a client, an employer, or even oneself. Wikipedia has an explanatory page about what to do in this situation, called the plain and simple conflict of interest guide, but its length suggests that it's anything but. Read it before you try.
Another factor affecting the success or failure of your intended change relates to how often the article in question is edited by others. Is the page edited every day, a few times a week, or much less often? In the first two instances, lots of eyeballs will be on your edit, so if another editor doesn't like it, they may undo—or "revert"—your change. But on less-traveled pages, your edit may stand for a long time—until someone shows up and decides otherwise. Or, is the page about a controversial subject? If so, check the article's discussion page first to see if your idea has been considered and rejected, and why. If not, then you may have a freer hand to make or suggest changes.
Notwithstanding all of the above, sometimes it is possible to be quite certain that you have it right by the rules and the sources, and you still find a Wikipedia editor disagrees with you. Maybe they don't know as much about the subject, maybe they have an agenda of their own, or maybe you've both come to the topic in good faith, but have nevertheless arrived at different conclusions. You can review their contribution history to try to understand their previous activity, but Wikipedia's editors are not required to give much information about themselves, so you may never know for sure.
Generally speaking, questions of fact are easier to resolve than matters of perspective. Anytime judgments not strictly informed by guidelines come into play, such as phrasing, or selecting specific points from a news story to highlight, the ultimate determinant is which editors choose to participate, what their views on the subject may be, and what compromise they can agree on. If you have ever wondered why there can be such a discrepancy between Wikipedia's stated rules and the actual results, this is often why.
Unfortunately, Wikipedia's rules can't anticipate everything, and into this gap steps another key principle: consensus. Joining notability and reliability as fuzzy concepts, this is is the notion that it's best for Wikipedia editors to agree on page content, and recommends methods for working together to achieve this. You'll want to know the discussion page guidelines, because consensus usually emerges through conversation. Also familiarize yourself with the "bold, revert, discuss" cycle of edits and discussion, which is treated as policy and aims to prevent edit wars. Being willing to find a compromise is one of the most important, and sometimes most difficult, principles of being an effective Wikipedia editor.
Everywhere throughout Wikipedia, the outcome of any specific change—to add, modify, or remove information—depends on these three key points: what the rules say about what you want to say, if you have sources to establish the facts as you see them, and whether there is consensus among Wikipedia editors that your desired change improves the encyclopedia.