A hard disk consists of two or more platters stacked on top of one another; so it has four or more sides with many more tracks per side than a diskette. (The number of tracks depends on the capacity of the hard disk. You do not need to know how many sides and tracks your hard disk has.)

A disk is further divided by sectors. To understand what a sector is, picture the spokes on a bicycle wheel radiating from the center of the wheel to the tire. The space between one spoke and the next is like a sector on a diskette; the lines dividing the sectors cut across the tracks. (See the figure below.) A diskette can have 8, 9, 15, or 18 sectors per track. The number of sectors on a hard disk depends on the type of hard disk.

track

Your computer uses the read/write heads in a disk drive to store and retrieve data on a disk. To write to a disk, the computer spins it in the drive to position the area on the disk where the data is to be written under the read/write head. A diskette has an exposed area where the read/write head can access it.

Using the Equity 386

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