Dark data is the inactive or unused information stored in your systems—often...

https://holdenlvxt779.theburnward.com/what-is-a-smart-data-migration-and-when-should-we-do-it

Dark data is the inactive or unused information stored in your systems—often 55% of all data. It increases storage and backup costs, sometimes wasting millions annually, and can expose you to ransomware or breach risks