Q: Versioning in iCloud Drive?

Versioning is a feature that saves previous versions of a file as you save it over time.  Everytime you save the file, a backup copy of that file is saved so you can go back in time.  I know with apps like MS Office you can tell it to save a backup copy of a file, but with Dropbox you can have 5 or even 10 prior versions of the file.  It's something that's definitely saved me in the past.

I don't really consider Dropbox a backup either, but it's a really handy feature.  I use Crashplan for backups.  I do like the idea of getting rid of a redundant app though.

Sorry, haven't tried restoring an entire library, just individual files.