data storage devices [1]
				   		Electronic devices used to record or save data on a magnetic or optical medium.
				
 
					
					
						removable hard disk 
						Case that contains a set of hard magnetic disks for insertion into a removable hard disk drive.
				  	
 
					
						removable hard disk drive 
						Stand-alone device that is connected by cable to a computer; it is used to read and write data on a removable hard disk.