You're probably wondering by now, "Why does my article need sources/references, anyway? I know everything I wrote is true." We can explain.
The goal of Wikipedia is not truth, but verifiability. (Yes, this means in certain circumstances we might use a "reliable source" that you think is not true.) References do two main things:
- References back up all the information in the article. For example, an article on Coca-Cola could have this sentence: Coke mini is a 7.5 ounce can packaging of Coca-Cola that debuted in December 2009.[1] If someone wanted to verify this fact, they could look at the reference that backs up this claim. This does not mean it's 100% proven, just that a trustworthy publication (in this case, The Atlanta Journal-Constitution) has said this and it wasn't just from some random Wikipedia user's imagination. Any statement(s) that do not cite a source may be removed at any user's discretion. Ideally, all non-obvious facts in an article should be supported by a reference. For example, "Coca-Cola is a carbonated soft drink" does not need a source, but "Coca-Cola was first sold at Jacob's Pharmacy in Atlanta, Georgia, on May 8, 1886" would need a source, because this is not widely-known, basic information.
- References show how the subject of the article is notable. On Wikipedia, notability (AKA why is something important enough to deserve a Wikipedia article) is defined in several ways, depending on the type of subject (such as an athlete, a company, a website, a band, etc.). However, the general notability guideline defines notability has having received significant coverage in reliable sources that are independent of the subject. If you include such sources, you are essentially proving that the subject of your article is an topic worthy of inclusion in Wikipedia (although there are some cases where the article would still not be appropriate for Wikipedia), and if no such sources exist, the subject of the article is likely not notable enough by Wikipedia standards. This doesn't mean that the subject is not important in real life, but that it/he/she/they simply do not meet Wikipedia's guidelines.
- I don't understand why other articles are allowed to not use reliable sources. I've even seen articles with no sources at all.
- Many articles on Wikipedia are not up to our standards. You are encouraged to improve low-quality articles, but just because they exist does not mean you should mimic them and use unreliable sources in your own article, as this only results in more articles with poor sourcing and less verifiability. If you want to use another article as a model to write your article, look at Wikipedia's best articles: WP:featured articles and WP:good articles. Both of these types of articles have gone through special quality review processes, and there are enough of them that you should be able to find one on a topic similar to your article's subject.
