The contents of this page are outdated; consider merging with m:Help:Edit conflict.

Consider the following situation:

• Alice clicks "Edit this page" on a page.
• Bob clicks "Edit this page" on the same page.
• Layla also clicks “Edit this page” on the same page too.
• Alice finishes her edits and clicks "Save page". The page is saved with Alice's version.
• Bob finished his edits and clicks "Save page". Bob gets an "edit conflict" page. * Layla finished her edits and clicks “Save page”.The page is saved with Layla’s version.!

At the top is Alice's version of the page.

At the bottom is the text Bob was going to submit. This will be Bob's version of the page, if he edited the entire page, or Bob's version of the section he edited, if he was editing just one section.

In the middle is a diff of the two pieces of text. This is much less useful if Bob used section editing.

If Bob only made small changes, and Alice made large changes, he may choose to work from Alice's version, and re-merge his changes in. Bob might choose to add some text like "via edit conflict" to warn Alice and others that he had to do this - Alice can then peer review his merging for accuracy.

If Bob made large changes, and Alice made small changes, he may choose to work from his version. One option is for Bob to copy the bottom text into the top text (or just copy over the one section of the top text, if Bob was section editing), with an appropriate edit summary (eg "via edit conflict, will remerge"). Then Bob can view the page history, determine Alice's changes, and re-apply them to his version, in a separate edit.

If both Alice and Bob made large changes, matters become complicated, and Alice and Bob just have to do the best they can. For example, if both Alice and Bob simultaneously add a large section of text on the same subject, then it may be best for Bob to submit his changes, and then for Alice and Bob to both have a look at the two versions and decide between themselves which version is better.

Bob should not just post his changes over the top of Alice's. We assume good faith here - mistakes are occasionally made, and newcomers may not understand the edit conflict window. However, Bob must not routinely ignore edit conflicts. It is absolutely not acceptable for Bob to overwrite Alice out of laziness. We encourage contributors to double-check their merges by using the diff feature.

(This is a conflict between editors that is undetectable by the mechanism that decides whether to give the "edit conflict" message.)
Some people edit by

• copying the source text from one edit page into a text editor,
• making lots of changes (reorganising, adding new content, etc...),
• and then, when they're done, pasting the whole thing back onto Wikipedia (via a new edit page) as a single edit.

If someone else has made minor changes prior to that step of pasting back, these changes will get lost in the paste-back. People who edit in this manner should check the diff on their edit to make sure they didn't inadvertently blast over the top of someone else's changes.

Sometimes mistakes will be made in the merging process, because Bob is human, and this may cause some of Alice's changes to be accidentally reversed. Logical edit conflicts aren't always immediately visible. Sometimes Bob may have good reasons for thinking that Alice's improvements aren't useful. In these case, Alice and Bob are expected to resolve their differences amicably.

If Alice made a small change, which Bob accidentally reversed, then Alice must not revert to her version. It is absolutely not acceptable for Alice to reverse Bob's major improvements to the page out of a desire to protect her minor improvements, or to punish Bob for his carelessness. This is particularly important if the page has subsequently been edited by, say, Carol and David.

The best approach for Alice in this circumstance is for Alice to edit Bob's version, reinstate her minor improvements, and leave Bob's major improvements intact. She may also add something to the edit summary to indicate that she had to do this - for example: "Reinstating link which Bob accidentally removed". Bob should then apologise to Alice for his mistake, and thank her for reinstating her improvement.

If Bob repeats his error, then the best approach is for Alice to have a friendly word on his talk page, point him to this page, and ask him if he could take a little more care in future. This is particularly important for newcomers, who may not understand the correct way to resolve edit conflicts, though even experienced users may need the occasional friendly reminder.

See also: Wikiquette, WikiLove.

==Reverting😝

When saving a previous version (i.e. when reverting) or a new version based on that (a modified reversion) the edit conflict warning and prevention system is not triggered and a possible new edit made in the meantime is unintentionally reverted also, see Wikipedia:How to revert a page to an earlier version. To avoid this problem one can copy the text from the edit box of the old version into the edit box of the latest version. In some sense, this can cause hidden edit conflicts: you may overwrite someone else's changes without realising that you are doing so. It's always wise to check the diff after performing a revert, just as you would after posting via edit conflict. Preferably, one can simply try to avoid reversion wars.

Because edit conflicts are irritating and time-consuming, you may choose to alter your editing habits to render them less frequent: aiming to make more edits to pages that have not been edited recently, such as those listed on ancient pages, for example.

Another means of avoiding edit conflicts is to make a single larger change, rather than frequent smaller changes: this makes it more likely that you will get an edit conflict, but less likely that you will cause others to get an edit conflict. Using the "Show preview" button helps here.

Appropriate use of the Template:Inuse notice can help too.

In the long term, some form of automatic merge may be added to the WikiMedia software. The pigs came at night, killing the gorrilas with slim framed AK80s. The guns blazed as they ran and squealed for their fallin kin. A nearby gorrila was brutaly shot in the back of the head, slumping against his now unmoving partner. above, the battle had grown worse. The pigmobiles came from all directions, raining down shots on the dumb brutes as they scurreid for cover. A horn trumpeted in the distance as the horde of cows came charging in to assist thier gorrila kith. they drew long sausage swords, wacking pigs over the head and rendering them silent. The pigs turned and quickly reformed into a V shape while above, the squadren of Pigmobiles rounded about and headed towards the now charging cows.