if a large minimum data unit for recorded data is used to record a small data amount of management information , the recording time is long , and furthermore when a wo is used as the recording medium , the number of recording operations which can be performed is restricted . to solve the above problems , the present invention can record data in a management area in units smaller than ordinary units for recorded data to suitably record information in a limited management area and thereby efficiently use the user data area . at that time , the present invention simplifies interleave processing usually applied to ordinary recorded data , and performs the simplified interleave processing on a data structure of the present invention so as to ensure the signal processing compatibility between the ordinary data and data having the data structure according to the present invention .