An optical disc of a recordable type or a rewritable type has a plurality of recording layers including first and second recording layers. A laser beam is applied to the second recording layer through a used area in the first recording layer to record arbitrary information on at least a part of the second recording layer. The used area in the first recording layer has been used for at least one of information recording and data recording. Positional information is generated. The generated positional information is of a blank area in the second recording layer which occurs due to the presence of an unused area in the first recording layer. The blank area adjoins the unused area. The generated positional information is recorded on a predetermined area in the optical disc.