Dark data is the information your company collects but doesn’t use or manage....

https://technivorz.com/how-do-i-stop-dark-data-from-polluting-our-ai-search/

Dark data is the information your company collects but doesn’t use or manage. It often makes up 55% of data stored, leading to wasted storage and backup costs. Plus, it increases ransomware and breach risks since unmanaged data is harder to protect