Dark data is the information your business collects but never uses, like old...

https://alpha-wiki.win/index.php/How_Do_I_Find_Former_Employee_Folders_That_Nobody_Owns_Now%3F

Dark data is the information your business collects but never uses, like old files or forgotten emails. Up to 80% of company data can sit inactive, taking up space and costing you money—sometimes over $2.5 million a year