Dark data is all the info stored but never used—like inactive files or old...

https://rapid-wiki.win/index.php/Why_Do_We_Keep_Paying_to_Store_Files_Nobody_Uses%3F

Dark data is all the info stored but never used—like inactive files or old backups making up 60% to 80% of data on company servers. It costs money to keep, increases security risks, and often clutters AI projects with noise that lowers accuracy