Co-authoring and document editing is a way of life in SharePoint 2013, 2016, and Online. But how it works remains a mystery to many. And you can't hold it against those people; how co-authoring works isn't obvious. This article covers the basics, how co-authoring works with version history, different versions of Office, and the limits to co-authoring's functionality. This article should be required reading for all SharePoint users.
Link: http://icansharepoint.com/co-authoring-its-a-date/
