Help:Reverting

Reverting means undoing the effects of one or more edits, which normally results in the page being restored to a version that existed sometime previously. More broadly, reverting may also refer to any action that reverses the actions of other editors.

This page contains technical information about making reverts. It should be borne in mind, however, that reverting good-faith actions of other editors (as opposed to vandalism) is considered disruptive when done to excess, and can even lead to the reverter being blocked from editing. Note particularly the three-revert rule (part of the Edit warring policy). Other Wikipedia essays on the subject include Reverting and Revert only when necessary.

Manual reverting
In some cases (for example, if a vandal added or removed text, and unrelated constructive edits have been made since) the easiest way to undo past edits may simply be to edit the current page, deleting wrongly added text or restoring wrongly deleted text (this can be copied and pasted from a past version of the page). However it may be more convenient to restore a particular old version of the page from prior to the changes you wish to revert. To do this:
 * Click the "history" tab at the top of the page to display the page history.
 * Click the time and date of the earlier version to which you wish to revert. You will see a phrase similar to: "This is an old revision of this page, as edited by ***.*.***.*** (Talk) at 15:47, January 24, 2009. It may differ significantly from the current revision."
 * Important: in the case of vandalism, take the time to make sure that you are reverting to the last version without the vandalism; there may be multiple consecutive vandal edits or they may be interspersed between constructive edits.
 * Click the "edit this page" tab as you normally would to edit a page. (Above the edit box, you will see a warning similar to: "You are editing an old revision of this page. If you save it, any changes made since then will be removed.")
 * Complete the edit summary field (the abbreviation "rv" can be used to stand for "revert"; the edit summary "rvv" means "reverting vandalism").
 * Save the page.
 * If constructive edits had been made after those that you wished to revert, return to the page history to find those edits, and redo them by hand if reasonably possible.

If reverting vandalism, check the contribution history of the user who vandalized the article. If this user is vandalizing many articles, report them to Administrator intervention against vandalism.

Undo
The MediaWiki software allow editors to easily revert (or "undo") a single edit from the history of a page, without simultaneously undoing all constructive changes that have been made since. To do this, view the page history or the diff for the edit, then click on "undo" next to the edit in question. The software will attempt to create an edit page with a version of the article in which the undesirable edit has been removed, but all later edits are retained. There is a default edit summary, but this can be modified before saving.

This feature removes the need to manually redo useful changes that were made after the edit which is being reverted. However, it will fail if undoing the edit would conflict with later edits. For example, if edit 1000 adds a paragraph and edit 1005 modifies that paragraph, it will be impossible to automatically undo edit 1000. In this case, you must determine how to resolve the problem manually.

For a proposal to restrict the availability of this function due to potential misuse, see Limit the undo function.

Rollback
Administrators and other editors who have been granted access to the rollback feature have additional links which:
 * appear only next to the top edit
 * revert all top consequent edits made by last editor
 * work immediately, without the intermediate confirmation diff page
 * add automatic edit summary "m Reverted edits by Example (talk) to last version by Example2", marking edit as minor

Rollback links appear on the user contributions pages, user watchlists, history pages and diff pages. Note that in the last case, rollback links can be misleading, since reversion is not necessarily to the old version shown (the diff page may show the combined result of edits, including some by other editors or only part of the edits the rollback button would revert). To see the changes the rollback button will revert, view the specific diff that compares the last version from the last editor with the last version from the previous editor.

Rollback works much quicker than undo, since it:
 * allows reverting without even looking at the list of revisions or diff
 * does not require loading an edit page and sending the wikitext back to the server
 * does not require a click of the save button

On the other hand, it is not as versatile as undo, since it does not allow specification of which edits have to be undone. One may want to revert more or less edits than the rollback does or edits which do not include the last edit. It also does not allow adding an explanation to the automatic edit summary. Rollback is supposed to be used to revert obvious vandalism.

Rolling back a good-faith edit, without explanation, may be misinterpreted as "I think your edit was no better than vandalism and reverting it doesn't need an explanation". Some editors are sensitive to such perceived slights; if you use the rollback feature other than for vandalism (for example, because undo is impractical due to the large page size), it is courteous to leave an explanation on the article's talk page or on the talk page of the user, whose edit(s) you have reverted.

If someone else edited or rolled back the page before you clicked the "rollback" link, or if there was no previous editor, you will get an error message.

Reverting images
In order to revert an image to a previous uploaded version, go to the image page and click on "File history". The File history section of the image displays the full history of edits to the image alongwith a thumbnail of each version. Logged-in users can see a "revert" link for every version other than the current version. Clicking on a version's revert link makes that version the current version.

Additional tools

 * Sam Hocevar's godmode-light.js script adds functionality similar to the admin rollback links described below. More info at WP:US.
 * Vandal edits can also be reverted using popups or monobook-suite.