By way of example only, FIG. 1A illustrates a hard disk drive 170 that reads from or writes to non-removable, nonvolatile magnetic media, a magnetic disk drive 180 that reads from or writes to a removable, nonvolatile magnetic disk 190, and an optical disc drive 191 that reads from or writes to a removable, nonvolatile optical disc 199 such as a CD ROM or other optical media.