Board Thread:Support Requests - Community Management/@comment-4721925-20131001145824/@comment-1997905-20131001152833

You can prevent anonymous editors from editing specific pages by protecting them, but note that it is a ToU violation to protect every page on your wiki indefinitely. You can easily revert any edit with the rollback button or the undo button next to the edit in RecentChanges, next to the user's name on the diff page, or next to any edit in the page's history. If this is not enough, you can ask staff to prevent all anonymous edits on your wiki at Special:Contact/general, but note that this is rarely ever done.