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It has several options for types of wiping in the Options>Settings section. It shows how many passes 1,3,7, or 35, but does not name them by name. 1 is usually a simple but ineffective method, 3 is usually DoD, 7 is yet another "secure method" and 35 is usually the Gutman method in several of the apps that I've tried/used. But since CCleaner chooses not to name names, it's anyone's semi-educated guess as to what they mean.