text: Store backups or file comparisons of each edit, so there are the previous versions of the file can still be accessed once the original is overwritten.
  File locking, which limits the file to one editor at a time to prevent edit conflicts. 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."
  Merge, by determining if the edits are in unrelated parts of the file and combining without user intervention.
  Occurrences
  The problem is encountered on heavily edited articles in wikis (frequency higher in articles related to a current event or person), distributed data systems (e.g., Google Sites), and  revision control systems not using file locking, 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paste the new text into a word processor or similar program for further editing, or can paste that text directly into a newer version of the target document.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.