Help:Reverting a page to an earlier version

To revert to an earlier version:
 * Go to the page, click on "Page history" in the sidebar (there are also "Page history" links on the bottom and top of every page), and click on the time and date of the earlier version you want to revert to. It will not work if you click on 'cur' or 'last'.
 * Then when that page comes up, you'll see something like "(Revision as of 23:19 Jul 15, 2003)" below the title, rather than "From {project name}".
 * Verify that you've selected the correct version, and click to edit the page, as you would normally.
 * You'll get a warning, above the edit box, about editing an out-of-date revision.
 * Ignore the warning and save the page. Be sure to add the word "revert" (or "rv") to the edit summary

Reverts and edit conflicts
Reverts never cause an edit conflict - if between you pressing edit, and then pressing post, someone else edits the page, their edits will be silently overwritten (though still in the page history). Beware of reverting high-traffic pages! Conversely, if it looks like someone has deleted your edits, consider if it's more likely that it's one of these unfortunate reversion conflicts.

Admin-only "rollback" link
On a user contributions page an admin has additional "rollback" links at lines which are also marked "top", i.e. the lines regarding edits of articles which are the last edit made by anybody to that article. Clicking on the link reverts to the last edit not authored by the user concerned, with automatic edit summary "Reverted to last edit by X".

If, between loading the User Contributions page and pressing "rollback" someone else has edited or rolled back the page already, one gets the message "Rollback failed" with explanation.

If the user concerned has created the page and been the only editor, even though a rollback link appears, clicking it gives the message "Cannot revert edit; last contributor is only author of this article."

This feature can not be used when the last two edits were by the same user, and one wants to revert the last one only.

The feature is especially useful in the case of a known vandal, whose edits one need not check anymore before reverting them.