Dark data is the information companies collect but never use—think of old...

https://wiki-byte.win/index.php/What_Is_Dark_Data_Management,_Not_the_Marketing_Version

Dark data is the information companies collect but never use—think of old files, logs, or emails just sitting around. It can make up 60-80% of all inactive data, taking up space and costing businesses an average of $2.5 million every year