Why have Community Wiki posts?
One of the goals of the website is to be a continually evolving source of good information. Community wiki posts help enhance the wiki aspect of the site.
For more information about the proper use of community wiki, see The Future of Community Wiki.
How do Community Wiki posts work?
Community wiki posts work by transferring ownership of the post from the original author to the community. They make the post easier to edit and maintain by a wider group of users, but they do not contribute to any user's reputation.
Some of the key features are:
- Community wiki posts are owned by the Community User 1, not by any individual user.
- A much lower reputation (100 instead of 2000) is needed to edit a community wiki post. 2
- Voting on a community wiki post (up or down) does not affect any user's reputation.
- Accepting an answer marked as community wiki does not affect its author's reputation.
- Bounties awarded to answer marked as community wiki give reputation as usual.
- The original author still gets badges based on community posts.
- The original author keeps the reputation gained (or lost) before their post entered community mode.
- The original author still receives notifications for edits or comments on the post.
How does a post become a Community Wiki post?
There are only three ways that a post becomes community wiki.
The answer's author checks the community wiki checkbox when composing or editing the answer. Note that this checkbox isn't available to new users. The checkbox also is not available if the question is already a community wiki. 3
A moderator has reason to believe that the post serves better in community wiki mode - if you believe your post should be converted to a community wiki, you may flag it for moderator attention.
An answer posted to a community wiki question will also be community wiki. In the past, questions could be made community wiki by their authors or by certain automatic triggers but now the only means is by a moderator converting it to community wiki. When a moderator converts a question to community wiki, all existing answers will also be converted in addition to converting future answers.
* note that the rules outlined above are based on the last time this post was updated; the actual behavior of SO is subject to change without notice, and may well have done so since this was last updated...
How can the Community Wiki status be removed from a post?
Moderators can remove it, when necessary. Once removed, the post will never be given the CW status automatically due to a high number of edits again.
Rollbacks cannot be used to remove community wiki status.
The Community User ¹ might appear as the last editor of a question, even a non-wiki question. This happens when it randomly pokes old unanswered questions so they get some attention.
1 See Who is the Community User?, or read the Community User’s profile.
2 The original author of a community wiki post can always edit it, even if he or she has ≤ 100 reputation.
3 Since October 2010, there is no community wiki checkbox when asking a question.