Question

what is overwriting and how it can be done in computer​

Answer 1

In computer data storage, overwriting is the process of replacing old information with new information. Overwriting generally occurs when unused file system clusters are written upon with new data, though overwriting is also used in security algorithms. These algorithms use a precise set of rules to remove any part of original data from the memory by writing new raw data on the memory. Data that has been overwritten, even just once, is generally considered to be unrecoverable.

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