One of the key policies of Wikipedia is that all article content has to beverifiable. This means thatreliable sources must be able to support the material. All quotations, any material whose verifiability has been challenged or is likely to be challenged, and contentious material aboutliving persons (whether negative, positive, or neutral) must include aninline citation to a source that directly supports the material. This also means that Wikipedia is not the place fororiginal work, archival findings that have not been published, or evidence from any source that has not been published.

If you are adding new content, it isyour responsibility to add sourcing information along with it. Material provided without a source is significantly more likely to be removed from an article. Sometimes it will be tagged first with a"citation needed" template to give editors a chance to find and add sources, but some editors will simply remove it because they question its veracity.

This tutorial will show you how to add inline citations to articles, and also briefly explain what Wikipedia considers to be a reliable source.