Wikipedia is an encyclopedia, a specific type of reference work properly containing articles on topics of knowledge. Wikipedia employs the concept of notability to avoid indiscriminate inclusion of topics by attempting to ensure that the subjects of articles are "worthy of notice" – by only including articles on topics that the world has taken note of by substantively treating them in reliable sources unconnected with the topic.

The general notability standard thus presumes that topics are notable if they have "received significant coverage in reliable sources that are independent of the subject".

In order to establish notability, we ask that users cite, using inline citatons, to reliable secondary sources that are independent of the topic and provide significant coverage of it beyond its mere trivial mention. If notability cannot be established for an article it is likely to be merged, redirected, or deleted.

There are a number of common mistakes seen in addressing this issue:

• Adding citations but to unreliable sources: We are looking for treatment in sources like mainstream newspaper articles, non-vanity books, magazines, scholarly journals, television and radio documentaries, etc. – sources with editorial oversight and a reputation for fact-checking and accuracy. This means generally not random personal websites, blogs, forum posts, Facebook, LinkedIn, Twitter, self-published sources like open wikis (including other Wikipedia articles), etc. In short, read and understand Wikipedia:Identifying reliable sources.
• Adding citations to connected (non-independent) sources: While primary sources may be useful to verify certain facts, they must be used with caution and do nothing to establish notability. In short, we are looking for secondary sources written by third parties to a topic.
• Adding citations to sources that merely mention the topic: You can cite numerous reliable, secondary, independent sources and it will not help establish notability if they do not treat the topic substantively – think generally two paragraphs of text focused on the topic at issue. Remember: it is much better to cite two good sources that treat a topic in detail, than twenty that just mention it in passing. Moreover, citation overkill to sources containing mere passing mentions of the topic is a badge of a non-notable topic and, if good sources are actually present in the mix, they will be hidden among these others from those seeking to assess a topic's demonstration of notability.

If insufficient reliable secondary and independent sources exist treating a topic in substantive detail, then Wikipedia should not have an article on the topic. Remember that no amount of editing can overcome a lack of notability.