Reading the text to augment the on-line lecture notes is a good idea. The level of the questions is likely to be at that of the short answer questions in the text. Secondary Storage Devices Secondary storage devices serve the same role as a library does for reading. Magnetic tapes - highest capacity, used to backup hard disks. Floppy disks Floppy disks used to be floppy - now they are encased in a hard shell, but inside the magnetic material is still flexible.
Magnets have north and south poles.
All magnetic media work by controling the orientation of the magnetic field. Standard 3.5 inch diskettes hold 1.4 megabytes each, although even higher densities are possible. Formatting Disks simply store patterns of bits, which can be accessed only by giving the appropriate address. We seek to access what is on the disk by their file names. To do this, there must be a place on the disk which for each file name records where on the disk it is.