an asperity data storage system wherein asperities are used to represent stored data . the asperity data storage system includes an asperity transducer that thermally interacts with a data storage medium adapted to store an information - encoded pattern of asperities thereon , such as a rotatable disk , a streamable tape , or a fixed medium . a drive system produces relative motion between the data storage medium and the asperity transducer , while electrical signals corresponding to the asperities are processed as stored information . a positional relationship can be maintained between the asperity transducer and the data storage medium using the asperities on the data storage medium for reference . a related asperity data storage method and the asperity data storage medium itself are further disclosed .