An edit conflict is usually where two users try to edit a page at the same time.

What happens, and how do I avoid edit conflicts with others?Edit

One of them will be told that there is a conflict due to someone else saving the page since they started editing it.

See Help:Edit conflict on Meta-Wiki for details on what happens, how to deal with edit conflicts, and advice on avoiding them.

How did I get in an edit conflict with myself?Edit

This occasionally happens if you edit, save, and then hit your browser's "Back" button to go back to the edit box. You can avoid it by using the "edit" button to open a new instance of the edit box rather than using "Back".