Terms used in Digital Forensic

Slack space is the unused space between the end of the actual file and the end of the defined data unit (cluster). A cluster is the least significant unit of storage that the operating scheme can deal with. When a document is in writing, and does not live at the whole cluster, the remaining space is slack space.

On the other hand RAM slack pertains only to the last part of a file. If added sectors are required to aaround out the block dimensions for the last cluster allotted to the document, then a different kind of ...