Data corruption is the accidental change of a file or the loss of information which often occurs during reading or writing. The reason may be hardware or software failure, and for that reason, a file can become partially or completely corrupted, so it'll no longer function properly as its bits will be scrambled or lacking. An image file, for example, will no longer show an authentic image, but a random mix of colors, an archive will be impossible to unpack as its content will be unreadable, and so on. In the event that such a problem occurs and it isn't noticed by the system or by an admin, the data will be corrupted silently and in case this happens on a drive that's part of a RAID array where the data is synchronized between different drives, the corrupted file shall be duplicated on all of the other drives and the harm will become permanent. A number of popular file systems either don't offer real-time checks or do not have good ones which will detect a problem before the damage is done, so silent data corruption is a very common matter on hosting servers where huge volumes of data are stored.