Data corruption is the unintentional transformation of a file or the loss of information that usually occurs during reading or writing. The reason could be hardware or software failure, and as a consequence, a file could become partially or fully corrupted, so it will no longer function correctly as its bits shall be scrambled or missing. An image file, for example, will no longer present a real image, but a random mix of colors, an archive will be impossible to unpack because its content will be unreadable, and so on. In the event that this kind of a problem appears and it's not noticed by the system or by an admin, the data will get corrupted silently and if this happens on a drive that's a part of a RAID array where the information is synced between various drives, the corrupted file shall be reproduced on all the other drives and the damage will become long term. Many popular file systems either don't feature real-time checks or don't have high quality ones that will detect a problem before the damage is done, so silent data corruption is a rather common problem on internet hosting servers where substantial amounts of information are stored.