Toshiba Satellite 200 Series, Руководство пользователя

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What’s Really Going On?
How Big Is a Megabyte, Anyway?
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How Big Is a Megabyte, Anyway?
When you read about the size of your hard disk, you may be con-
fused by the discrepancy between megabytes and millions of
bytes. “Wait a minute,” you say, “doesn’t a megabyte equal one
million bytes?” Well, not exactly...
Computers use base two arithmetic, also called binary arithmetic.
Because of this, all numbers in computing are based on powers of
two. One megabyte is actually equal to 1,048,576 bytes (2
20
), the
closest binary number to 1,000,000.
In the early days of personal computers, the difference was very
minor because hard disks were small and computers didn’t have
much memory. As hard disk capacities and memory sizes have
increased, the difference has become much more significant.
The hard disk that comes with the Satellite 200 Series computer
holds approximately 772 megabytes. You can convert this to mil-
lions of bytes by multiplying the number of megabytes (772) by
the number of bytes in a megabyte (1,048,576). The result is
809,500,672, approximately 810 million bytes.
How Does the Screen Display Information?
Images on the Satellite 200 Series computer's built-in liquid crys-
tal display (LCD) are created by turning individual dots on the
screen on or off in various combinations. These dots are called
pixels.
A pixel on the display
A pixel is the smallest element on the screen. On a color display,
each pixel is made up of three subpixels: one red, one green and
one blue (RGB). Each subpixel may be either on or off. Mixing on