disk image

A disk image is a computer file containing the complete contents and structure of a data storage medium or device, such as a Hard drive, CD or DVD. The term has been generalized to cover any such file, whether originated from an actual physical storage device or not. As such, a disk image contains all the information necessary to replicate the structure and contents layout, as well as the actual contents, of a storage device, and this is the distinguishing feature between an ordinary backup and a disk image. A disk image file is usually created based upon the sectors on the medium, ignoring its filing system.
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