To improve common understanding about security issues, the importance of classifying the information is stressed, after describing briefly the social background concerning privacy-related problems in Japan. We discuss here the classification only from the following two points of view: (a) the ownership; and (b) how to use. We will derive a two-dimensional fuzzy membership function to describe the ownership and a 'how to use' three-dimensional one as models for describing the framework concerning access right and informed consent.