Data corruption is the damage of data caused by various hardware or software problems. The moment a file gets corrupted, it will no longer function as it should, so an app will not start or will give errors, a text file shall be partially or entirely unreadable, an archive will be impossible to open and unpack, etc. Silent data corruption is the process of information getting harmed without any identification by the system or an administrator, that makes it a serious problem for website hosting servers as failures are very likely to occur on bigger hard disk drives where significant volumes of information are placed. If a drive is a part of a RAID and the data on it is replicated on other drives for redundancy, it's likely that the damaged file will be treated as a standard one and it'll be duplicated on all drives, making the damage permanent. A lot of the file systems which run on web servers today often are not able to identify corrupted files in real time or they need time-consuming system checks during which the server is not operational.