The data recovery process varies, depending on the circumstances of the data loss, the data recovery software used to create the backup and the backup target media. For example, many desktop and laptop backup software platforms allow users to restore lost files themselves, while restoration of a corrupted database from a tape backup is a more complicated process that requires IT intervention. Data recovery services can also be used to retrieve files that were not backed up and accidentally deleted from a computer's file system, but still remain on the hard disk in fragments.
Data recovery is possible because a file and the information about that file are stored in different places. For example, the Windows operating system uses a file allocation table to track which files are on the hard drive and where they are stored. The allocation table is like a book's table of contents, while the actual files on the hard drive are like the pages in the book.
