Recording device, recording method, reproducing device, and reproducing method

Abstract

To enable a physically rewritable disc to be appropriately used as a write-once type. When the rewritable disc is used in rewritable application, the position where writing of a predetermined data unit (for example, an ECC block) in data is started is set to a first position with respect to a reference position to record or play back the data. In contrast, when the rewritable disc is used in write-once application, the position where writing of the predetermined data unit in the data is started is set to a second position different from first position to record or play back the data. The position where writing of the data is started in the rewritable application is shifted from the position where writing of the data is started in the write-once application to disable rewriting of the data recorded on a rewritable recording medium when the rewritable recording medium for the write-once application is loaded in a recording-playback apparatus that does not assume the use of the rewritable recording medium in the write-once application.