Data corruption is the damage of info because of various software or hardware fails. The moment a file is damaged, it will no longer work accurately, so an application will not start or will give errors, a text file will be partially or completely unreadable, an archive file will be impossible to open and then unpack, etc. Silent data corruption is the process of info getting harmed without any identification by the system or an admin, which makes it a significant problem for hosting servers as fails are more likely to happen on larger hard drives where substantial volumes of information are placed. In case a drive is part of a RAID and the info on it is copied on other drives for redundancy, it is more than likely that the bad file will be treated as a standard one and will be duplicated on all of the drives, making the damage permanent. Lots of the file systems that run on web servers nowadays often are unable to locate corrupted files right away or they need time-consuming system checks during which the server isn't operational.