Toshiba Satellite 200 Series, User Manual

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What’s Really Going On?
How Does the Screen Display Information?
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The video mode required by a program depends on:
❖
whether the program displays graphics or text.
❖
the resolution required for the text or graphics.
❖
the number of colors used.
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the font size (in pixels) of the text.
Based on these requirements, computers recognize two categories
of video modes: graphics modes and text modes.
In a graphics mode, programs can turn on and off individual pels
to display a variety of images. The computer controls every pel on
the screen individually. This provides maximum display flexibility
while somewhat reducing the speed at which the display produces
images.
An image produced this way could be a drawing or picture, like a
pie chart, graph or photograph. It could also be an icon or a varia-
tion on a text character, like italics or bold type.
Windows 95 and Windows programs use graphics modes.
Character cell in a text mode
In a text mode, a character cell is the smallest element a program
can control. A character cell is a grid of pels. All cells are the same
size. Each cell displays a single letter or symbol. Character cells
are arranged in rows and columns. In a text mode, only characters
from a predefined set are available. If your program uses a text
mode, refer to the program's documentation for a list of available
characters.