not vandalism, and in some cases, that a source to verify accuracy is provided. This is in an effort to prevent inaccurate and potentially damaging information about living people from appearing on the site. ClueBot NG The most well-known "bot" that fights vandalism is ClueBot NG. The bot was created by Wikipedia users Christopher Breneman and Cobi Carter in 2010 (succeeding the original ClueBot created in 2007; NG stands for Next Generation) and uses machine learning and Bayesian statistics to determine if an edit is vandalism. While the bot has been effective in helping keep Wikipedia clean, some claim the bot is hostile to new users by not being able to apply a human brain's knowledge to the edit, and leaving impersonal . Blacklisting The MediaWiki title blacklist extension prevents page move vandalism and creation vandalism by using regular expressions to identify bad titles. Titles on the blacklist can only be created by or moved to by administrators. Pages that are also created repeatedly can be protected to prevent vandals from recreating bad pages. In addition to the title blacklist, the spam blacklist prevents external link spamming, a form of vandalism. New/unregistered users who want to add external links are required to answer a CAPTCHA. The "bad image list" prevents images that could be used to vandalize pages from being inserted, such as images with sexual content. Images on the list can be added only to pages where the use of the image is explicitly allowed. The entirety of the MediaWiki namespace, the main page, and high-risk templates are protected to prevent high server load and sudden interface changes. The edit filter can also prevent vandalism by disallowing the bad edit altogether, or by allowing only autoconfirmed users or administrators to perform the edit. Notable acts of vandalism Seigenthaler incident In May 2005, a user edited the biographical article about John Seigenthaler, Sr. so that it contained several false and defamatory statements. The inaccurate claims went unnoticed between May and September 2005, after which they were discovered by Victor S. Johnson, Jr., a friend of Seigenthaler. Wikipedia content is often mirrored at sites such as Answers.com, which means that incorrect information can be replicated alongside correct information through a number of websites. Such information can develop a misleading air of authority because of its presence at such sites: Stephen Colbert Comedian Stephen Colbert made repeated references to Wikipedia on his