Data corruption is the damage of data due to various software or hardware problems. Once a file gets damaged, it will no longer work correctly, so an application will not start or shall give errors, a text file shall be partially or completely unreadable, an archive file will be impossible to open and unpack, etc. Silent data corruption is the process of information getting harmed without any acknowledgement by the system or an administrator, which makes it a serious problem for hosting servers as failures are very likely to occur on larger in size hard disks where considerable volumes of information are located. If a drive is a part of a RAID and the data on it is duplicated on other drives for redundancy, it's very likely that the damaged file will be treated as a good one and will be duplicated on all drives, making the damage permanent. Lots of the file systems which operate on web servers nowadays often cannot identify corrupted files instantly or they need time-consuming system checks through which the server isn't working.