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