What is "edit conflict"

n. (context computing English) An error that occurs where a computer program allows multiple users to make changes to text, and two or more users simultaneously attempt to make such a change, but only one change is successfully made.

An edit conflict is a computer problem where multiple editors cannot all edit the same item during a short time period. The problem is encountered on wikis or distributed data systems.

Michael Antonovich (2010).
Office and SharePoint 2010 User's Guide: Integrating SharePoint.
p. 321 (752 pages), quote: "Edit conflict on a list linked to SharePoint".

An edit conflict occurs when a shared document is being edited by more than one person at the same time, and the attempted changes are treated as incompatible with each other. One person attempts to edit the document, but upon trying to save the new version, another person has already modified the document in the intervening time period, thus causing a difference between the attempted edit and the already-made edit that must be resolved manually, and causing an "edit conflict" error message. Computer writer Gary B. Shelly notes that many wiki systems "will block the contributor who is attempting to edit the page from being able to do so until the contributor currently editing the page saves changes or remains idle on the page for an extended period of time."

The problem can occur when working on heavily edited articles on Wikipedia, such as those about a current event or a person suddenly in the news, as well as other high-traffic pages. If a significant amount of new text is involved, the editor who receives an "edit conflict" error message can cut and paste the new text into a word processor or similar program for further editing, or can paste that text directly into a newer version of the target document. Simple copyediting can be done directly on the newer version, and then saved.

Edit conflicts can also arise when two or more editors are working on Google Sites, or when two or more users simultaneously edit the same file in a revision control system which does not have file locking.