User:0
Although the user 0 is a real editor (not a bot), the edits attributed to that username from 2002 were made by several Wikipedia users. This is due to a bug in a very early version of MediaWiki, where if a user made an edit some time between 20 July and 24 July 2002, all the previous edits to that page by registered users (including those by Conversion script) would be re-attributed to User:0, and all the edits by anonymous users would have their IP addresses truncated (for example, see the contributions of User:11.105). Edits made before 25 January 2002, during the UseModWiki era of Wikipedia, were imported in September 2002, so were unaffected by this bug. In the case of registered users who have had their edits attributed to this username, the editors' user ID's have been preserved, so it is theoretically possible to re-assign many of the edits back to the correct usernames. As a result, unlike most users, User:0 has several user ID numbers in the Wikipedia database.
