Abstract: An optical disk has a recording region divided into zones, each zone including physical tracks which are divided into a number of sectors. The optical disk further includes a structure management table which stores an attribute for each zone indicating whether the corresponding zone is a recording area which permits rewriting of a recording area that does not permit rewriting.

Abstract: According to the present invention, an apparatus for optically performing recording of information and/or reproduction of information for an optical disk having a recording surface is provided. The apparatus includes: an optical pickup for forming a first light spot on the recording surface; a tilt sensor, arranged to be transported with the optical pickup, for detecting a tilt of the optical disk with respect to an optical axis of the optical pickup by forming a second light spot on the recording surface; and a tilt compensating mechanism for angularly adjusting the optical pickup to eliminate the tilt. In this apparatus, the second light spot is formed at such a position that a line between the first and second light spots is inclined to a direction perpendicular to the radial direction of the optical disk.