Is there a way to identify a previously "unknown" visitor?

[Jem1]

Hi

I'm trying to build some marketing reports/lists and I need a way to identify that a user has not previously engaged with any content, whether this is a form submission or email interaction. 

And similarly that they were previously "unknown" i.e. they were not already a contact in our database.

I've tried filtering but I seem to be drawing a blank. Any help much appreciated!



EDIT - Solved myself by using date created

[JessicaH]

Thanks for sharing @Jem1!