CONTENT USING METHOD, CONTENT USING APPARATUS, CONTENT RECORDING METHOD, CONTENT RECORDING APPARATUS, CONTENT PROVIDING SYSTEM, CONTENT RECEIVING METHOD, CONTENT RECEIVING APPARATUS, AND CONTENT DATA FORMAT

A method of using contents includes the steps of setting public time information and private time information, the public time information being associated with each content and defined universally for use by a large number of unspecified users, the private time being associated with the content and defined for use by a small number of particular persons, and searching for a content according to the public time information and/or the private time information and using the content detected in the searching.