stored. Double-density diskettes have either 40 or 80 tracks, and high-density diskettes have 80 tracks. The double-density, 360KB diskettes you use in your Apex have 40 tracks.

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.

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. (See the figure below.) The diskettes you use on the Apex have 9 sectors per track; other types of diskettes can have 8, 15, or 18 sectors. The number of sectors on a hard disk depends on the type of hard disk.

Using Your Computer

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