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What's Really Going On?
How Does the Screen Display Information?
How Does the Screen Display Information?
Images on the computer's built-in liquid crystal display (LCD) are
created by turning individual dots on the screen on or off in vari-
ous 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
and off subpixels is like blending the primary colors to create other
colors.
A pel formed by several pixels
The smallest element that your programs can control is called a
pel. Pels are arranged on the screen in a grid-like fashion. Depend-
ing on the video mode a program selects, a pel may be a single
pixel or several pixels.
The pel size determines the clarity of the image—called screen
resolution. Larger individual pels reduce the total number of avail-
able pels, resulting in lower resolution. Smaller pels increase the
number of pels that can fit on the screen, resulting in higher resolu-
tion and a clearer image.
Part I: Getting To Know Your Computer