Dark data is the untouched information stored in your systems—up to 55% of all...

https://www.bright-bookmarks.win/dark-data-is-the-hidden-info-your-team-isn-t-using-about-55-of-stored-data-is

Dark data is the untouched information stored in your systems—up to 55% of all data goes unused. This matters because it racks up costs and creates risk, especially when AI sifts through cluttered files