Dark data is the inactive or unused information organizations accumulate, often...

https://www.jelly-bookmarks.win/dark-data-is-the-information-organizations-collect-but-don-t-use-often-making

Dark data is the inactive or unused information organizations accumulate, often making up 55% of stored data. It raises breach and ransomware risks since unmonitored files may hold vulnerabilities. Storing this data also wastes money—sometimes $2