Dark data is all the information companies collect but never use, like old...

https://touch-wiki.win/index.php/What_Does_%E2%80%9CData_Stays_Where_It_Lives_Until_Needed%E2%80%9D_Mean_in_Practice%3F

Dark data is all the information companies collect but never use, like old files or unseen logs. It's huge—up to 80% of stored data can go untouched. That’s a big deal because managing this forgotten data can waste around $2.5 million each year