A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
This is a good article to deal with recovering files. It's about Microsoft Word, but the same idea applies to PowerPoint and Excel, as well:
How To Recover Unsaved Or Lost Word Documents On Mac - Macworld UK
If you want to use automatic versions, the AutoSave is the way to go. Use File > Save As and choose OnLine locations (either OneDrive or SharePoint) to turn AutoSave on.