Epson Endeavor - Manual (Page 22)

How Disks Store Data
Diskettes are made of flexible plastic coated with magnetic
material. This plastic is enclosed in a square jacket that is either
hard (M-inch diskette) or slightly flexible (5.25-inch diskette).
Unlike a diskette, a hard disk is rigid and fixed in place. It is
sealed in a protective case to keep it free of dust and dirt. A
hard disk stores data the same way that a diskette does, but it
works much faster and has a much larger storage capacity.
All disks are divided into data storage compartments by sides,
tracks, and sectors. Double-sided diskettes store data on both
sides. On each side are concentric rings, called tracks, on which
a disk can store data.
A disk is further divided by sectors, which can be visualized as
pie slices. The illustration below provides a simple
representation of tracks and sectors.
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