system image

In computing, a system image is a serialized copy of the entire state of a computer system stored in some non-volatile form, such as a binary compressed file.
If a system has all its state written to a disk (i.e. on a disk image), then a system image can be produced by copying the disk to a file elsewhere, often with disk cloning applications. On many systems, such as some embedded devices and many phones, a complete system image cannot be created by a disk cloning program running within that system because information can be held outside of disks and volatile memory, for example in non-volatile memory, such as boot ROMs, or disk cloning program usually has no such privileges.
A system is said to be capable of using system images if it can be shut down and later restored to exactly the same state. In such cases, system images can be used for backup.
Hibernation is an example that uses an image of the computer's entire RAM.

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