The clear method applies logical techniques to every user-addressable location of an ISM to protect against simple, non-invasive recovery through the same interface the user has; it is never appropriate for hard copy and normally leaves the ISM usable. Typical techniques are overwriting with non-sensitive data through standard read and write commands, including file metadata, or a menu reset to factory state where rewriting is unsupported. Historic multi-pass overwrite schemes give little protection on media such as SSDs with overprovisioning and are to be avoided; purge or destroy is used where more assurance is needed. Overwriting cannot be used on non-rewriteable or inoperable media and cannot reach spare cells on wear-levelled flash, so users carrying magnetic-era habits onto flash devices increase their disclosure risk. Dedicated sanitize commands reach all storage areas more effectively but rely on vendor assurance that they work as intended. For devices such as basic phones or office equipment that only offer a factory reset, that reset still meets the clear definition provided the user interface cannot retrieve the original data.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.