Dark data is all the information your company stores but rarely uses—think...

https://foxtrot-wiki.win/index.php/How_Do_I_Get_Visibility_Into_Data_Across_Storage_Silos%3F

Dark data is all the information your company stores but rarely uses—think files sitting untouched on old servers. Around 55% of data falls into this category, costing businesses about $2.5 million a year in storage and management