|This page in a nutshell: Don't use edits to fight with other editors. Disagreements should be resolved through discussion.|
An edit war occurs when editors who disagree about the content of a page repeatedly override each other's contributions. Editors engaged in a dispute should reach consensus or pursue dispute resolution rather than edit war. Edit warring is unconstructive, creates animosity between editors, makes consensus harder to reach, and causes confusion for readers. Users who engage in edit wars risk being blocked or even banned. An editor who repeatedly restores their preferred version is edit warring, regardless of whether those edits are justifiable. Claiming "My edits were right, so it wasn't edit warring" is not a valid defense.
There is a bright line known as the three-revert rule (3RR). To revert is to undo the action of another editor. The 3RR says an editor must not perform more than three reverts, in whole or in part, whether involving the same or different material, on a single page within a 24-hour period. Any appearance of gaming the system by reverting a fourth time just outside of the 24-hour slot may also be considered edit warring. There are certain exemptions to 3RR, such as reverting vandalism or clear violations of the policy on biographies of living persons; see below for details. The three-revert rule is a convenient limit for occasions when an edit war is happening fairly quickly, but it is not a definition of "edit warring", and it is perfectly possible to engage in an edit war without breaking the three-revert rule, or even coming close to doing so.