An optical card (1) for storing a large amount of data in an optically readable manner, includes a plurality of tracks (TR) formed in a data record layer (1b) in parallel with each other, each track (TR) being divided into a data record area (4) and an address record area (3), and identifiers (ID) each recorded in address record areas (3) of respective tracks. By optically reading the identifier from the optical card, it is possible to recognise automatically the track construction denoting the number of sectors per track and the number of bytes per sector, thereby enabling optical cards with different track constructions to be used automatically.