If you are interested in the theory behind the operation, or are looking for more detailed information about file erasing, this section should give you all the answers you need.
The Advanced Topics start by explaining some of the terms most commonly used and continues by explaining why and where to overwrite and what kind of data to use. The discussion is continued with a detailed description of the overwriting methods used in Eraser and finished off with the complete paper "Secure Deletion of Data from Magnetic and Solid-State Memory" by Peter Gutmann.
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