Dark data is the 55% of stored information left unused and unmanaged in your...

https://www.bookmarking-fox.win/dark-data-refers-to-the-55-of-stored-information-that-organizations-collect

Dark data is the 55% of stored information left unused and unmanaged in your systems. It wastes storage and backup resources, costing companies up to $2.5 million a year. Left unchecked, dark data increases your risk of ransomware attacks or data breaches