Cartridge type recording medium and disk-shaped recording medium including a hole for centering each thereof, cartridge, driving unit and driving method

The object of the present invention is to provide a technology which has high compatibility and can provide users with conveniences. A new system recording medium has a center hole formed on a recording disk and a center hole formed on a center hub , so that the recording medium can respond to both an old system driving unit having a centering member coupling with the center hole and a new system driving unit having a second centering member coupling with the center hole . Moreover, the old system recording medium is a recording medium providing a recording disk having a center hole incorporated in a cartridge having a center hub, and has a structure where the center hole is coupled both with a first centering member of the new system driving unit and with the centering member of the old system driving unit.