Help:Revert a page
Reverting is changing a Wikipedia page back to an older version of the page. Because Wikipedia can be changed by anybody, the MediaWiki software is designed to save every version of a page when it has been changed by someone. When a new version of the page is saved, the old version is kept in the page's change history, so that anybody can see who changed the page, when they did it, and what changes they made to the page. You can change the page back to any of the old versions in the page history, such as when something has been added or removed when it should not have been.
How to revert
- Go to the page that is to be reverted and click on "history" to see the change history.
- Click on the time and date of the earlier version you want to revert to. (The 'cur' or 'last' links can be used to see what changes have been made to the page, but the next step will not work.)
- You will see something like "(Revision as of 07:52 January 28, 2015)" below the title. Make sure this is the version you want to save, then click "edit" at the top of the page, as you would normally.
- You will get a warning, above the edit box, about editing an out-of-date revision. Ignore the warning and click "publish changes" to save the old version of the page.
Be sure to add the words "revert", "undo", or "rv" to the change summary so that other editors know what is happening. It is also helpful to other editors to say which version you are reverting to, and why you are doing this.
Most reverts are usually for dealing with vandalism and other kinds of disruptive changes. It is not a good idea to do this just because you don't like what someone did to a page, especially if they were trying to make the page better instead of harming it. If this happens, instead of reverting, try to find a compromise (something you can both agree on) by talking about the issue on an article's 'talk' page.
Newer versions of MediaWiki have allowed editors to revert a single change from the history of a page without undoing all changes that have been made since the change that was reverted. This is called undoing.
To do this, go to the "diff" page for the change (which shows what specific change has been made from the last version), and click the 'undo' link above the newer version. The software will try to create a change page with a version of the article in which the unwanted change has been removed, but all later changes are kept. If this can be done, a change summary will be already created, linking to the contributions and talk page of the user whose change is being undone. This message can be changed or added to as necessary. The text editor also appears, so it is possible to make more changes to the page before saving.
The undo feature removes the need to manually redo useful changes that were made after the change which is being reverted. However, it will fail if undoing the change would conflict with later changes. For example, if change 1000 adds a paragraph and change 1005 changes that paragraph, it will be impossible to automatically undo change 1000. In this case, the change has to be removed manually, and the text editor which appears allows this to be done easily.
When you undo an edit, the person whose edit you are reverting gets notified that their edit was reverted. This helps editors who contribute in good faith resolve differences of opinion.
Reverts and change conflicts
Reverts never cause a change conflict. If you revert a page the same time someone else changes the page, you can overwrite their changes without knowing. Be careful reverting pages when lots of people are changing it at once.
Rollback is a MediaWiki feature that automatically reverts a page to the last change made by a different user with a single click. It is especially useful for vandals who make many bad changes one after another, as it reverts all of their edits at once.
The rollback feature can be used by all Wikipedia administrators and other logged-in editors who have been given the "rollback" right by any administrator. These users can see "rollback" links on the page history. Clicking on the link will immediately revert the page to the last change made by a different user. The change summary will say "Reverted edits by X to last version by Y", with links to the contributions and talk page of the user who is being reverted. The edit will appear as a minor change in the page history.
If someone else has already reverted the page, an error message will appear.
In cases of flood vandalism (lots of vandalism by one user in a short time), administrators can hide the vandalism from recent changes. To do this, add &bot=1 to the end of the URL used to access a user's contributions. For example, http://en.wikipedia.org/w/index.php?title=Special:Contributions&target=BadVandal&bot=1.
When you click the rollback links, the revert, and the original edit that you are reverting will be hidden from the default Recentchanges display. It does this by marking the edits as "bot edits" (edits by a robot), which are hidden from recent changes.
The edits are not hidden from contributions lists, page histories or watchlists. The edits are still in the database and are not removed, but they no longer show up on Recentchanges. This is done so flood vandals do not annoy people using recent changes. This should not be used for reverting a change you just don't like, but is meant only for massive floods of simple vandalism.
A revert war, or change war, is where two or more people keep on reverting to their own version. Revert wars do not help the aims of Wikipedia. They look bad, upset people and make the page history less useful.
Reverts should not be used for change wars. Use the talk page to discuss the problem and find something you can agree on.
Ask other people what they think. Perhaps they can change the words of the text to stop the change war. If it does not stop, ask an administrator to protect the page. You can ask this on Wikipedia:Simple talk, or on the Wikipedia:Administrators page, under the "current issues" section.