Then, the system reads data in a plurality of {HEAD ~ sectors} of the disk drive and saves the data to {TAIL ~ the free memory space} with a reading routine 
Then , the system reads data in a plurality of { HEAD ~ sectors } of the disk drive and saves the data to { TAIL ~ the free memory space } with a reading routine
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH