Dark data is all the untapped information your company collects but never uses....

https://yenkee-wiki.win/index.php/What_Does_%22Data_Stays_Where_It_Lives_Until_Needed%22_Mean_in_Practice%3F

Dark data is all the untapped information your company collects but never uses. It can be 60-80% of your stored data just sitting there, quietly eating up space and resources. Ignoring this data costs businesses an average of $2