Data corruption is the accidental transformation of a file or the loss of information which usually occurs during reading or writing. The reason can be hardware or software malfunction, and as a consequence, a file can become partially or entirely corrupted, so it will no longer work properly because its bits shall be scrambled or lacking. An image file, for example, will no longer show an accurate image, but a random combination of colors, an archive will be impossible to unpack because its content will be unreadable, etcetera. In case such a problem occurs and it isn't noticed by the system or by an administrator, the data will get corrupted silently and if this happens on a disk drive which is part of a RAID array where the data is synchronized between various drives, the corrupted file shall be duplicated on all of the other drives and the damage will become long term. A large number of commonly used file systems either don't have real-time checks or don't have good ones which can detect a problem before the damage is done, so silent data corruption is a common problem on internet hosting servers where substantial volumes of info are kept.