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

A cartridge type recording medium capable of recording and/or reproducing by use of a first driving unit containing a centering member and a second driving unit containing a centering member, comprising:

• a recording disk in which a first hole is provided for centering to the first driving unit with the centering member of the first driving unit abutting to the center portion of the recording disk;
• a cartridge housing the recording disk and including a shutter capable of opening/closing;
• and
• a hub held by the cartridge in a movable state in a direction of a diameter of the recording disk, which is constituted to be smaller in diameter than the first hole, which is capable for the centering member of the second driving unit to be inserted into, and in a center portion of which a second hole provided for centering to the second driving unit,
• wherein when the cartridge type recording medium is loaded on the first driving unit having the centering member, the centering member of the first driving unit is inserted into the first hole formed in a center of the recording disk.