The most fail-safe method of data recovery is to create data backups. Data backup copies the computer’s information, so that these copies can be restored through a data recovery process after a fatal event. Backups are useful mainly for two purposes: to restore a computer to an operational state following an accident (also called disaster recovery), and to recover information files after they have been deleted or corrupted (file or data recovery). Backups are normally the last defence against data loss (but also the most important one); they need time and consequently are hence the least convenient to use. The more important the data is, that is stored on the computer, the greater the need for backing up the data. Also, the probability of having to go through the data recovery process increases with the amount of information that is stored.