A data transfer apparatus referred to as a primary-recording-medium apparatus implements proper system operations by acquisition of information on a secondary recording medium mounted on a secondary-recording-medium apparatus to serve as a destination of a transfer (or a check-out) of a content. If a medium adopting its own unique management technique as is the case with a mini disc is used as the secondary recording medium serving as a destination of a check-out, the primary-recording-medium apparatus acquires information on the secondary recording medium from the secondary-recording-medium apparatus, which is typically a data-recording apparatus. The information includes an indicator as to whether or not the secondary recording medium has been mounted on the data-recording apparatus, the name of the secondary recording medium, the name of each content stored in the secondary recording medium, the number of contents stored in the secondary recording medium and attributes of each content stored in the secondary recording medium.