Reliable sources, generally, are third-party published sources with a reputation for fact-checking and accuracy. The best sources have a professional structure in place for checking or analyzing facts, legal issues, evidence, and arguments. The greater the degree of scrutiny given to these issues, the more reliable the source. Questionable sources are those that have a poor reputation for checking the facts, lack meaningful editorial oversight, or have an apparent conflict of interest. Self-published sources are generally not accepted as reliable sources. For a full discussion on what is and what is not a reliable source, see [[Wikipedia:Identifying reliable sources]].
* product instruction manuals or specifications.
Product, event, and restaurant reviews (i.e. where author describes personal opinions and experiences) must be handled with great care and diligence. Some types of reviews have a longer history and established traditions (e.g. restaurants, wine, books, movies), while other (e.g. new tech gadgets, travel blogs) are newer and more prone to manipulation by marketing and public relations personnel. Like any other source, reviews must meet the primary criteria to be counted towards the notability requirement:
#Be reliable: the reviews must be published in reliable sources that provide editorial oversight and strive to maintain objectivity. Self-published reviews (e.g. most blogs) do not qualify.
[[WP:NOTADVERTISING|Advertising]] is prohibited as an official Wikipedia policy. Advertising should be removed by following these steps, in order: