COUNTER TRACK

optical disks; optical data carriers; apparatus for recording optical disks; apparatus for reading optcial disks; data storage devices which include optical disks, magnetic disks, apparatus for recording optical disks, apparatus for recording magnetic disks, apparatus for reading optical disks and apparatus for reading magnetic disks; and computer software for controlling optical disks, magnetic disks, optical data carriers, magnetic data carriers, apparatus for recording optcal disks, apparatus for recording magnetic disks, apparatus for reading optical disks, apparatus for reading magnetic disks and data storage devices as data storage devices are defined above