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Unformatted text preview: oard. One such
example is the Dvorak keyboard. It has not been widely accepted, however, because most
people have already learnt and got used to the QWERTY keyboard layout.
As shown in Figure 9.2, the keys of a QWERTY keyboard are grouped into the following
functional groups to make the keyboard easier and more comfortable to use:
Alphanumeric Keys. The alphanumeric keys contain the keys for the letters of
English alphabet, the numbers 0 to 9, and several special characters like ?, /, $, &, @, etc.
As already mentioned, the arrangement of these keys follows the QWERTY layout.
Numeric Keypad. The numeric keypad is a set of keys that looks like an adding
machine with its ten digits and mathematical operators (+, -, » and /). It is usually
located on the right side of the keyboard. Notice from Figure 9.2 that the ten digits and
the mathematical operators keys, which form the numeric keypad are also present in the
set of alphanumeric keys. This makes the numeric keypad redundant. However the
numeric keypad is still provided because it permits rapid entry of numeric data. As it is
redundant, numeric keypad is usually not provided on portable PCs (laptops) due to space
limitations. 3. Arrow Keys. Arrow keys are a set of four keys - up (T), down (I), left (<-) and right
(->). They are also called cursor-control or cursor-movement keys because they are
mainly used to move the cursor at a desired location on the terminal screen connected to
the keyboard. A cursor, which usually appears as an underscore (_), a vertical line (|), or
a rectangle (■) on the terminal screen, always indicates the location of the next keyed-in
character on the screen. The arrow keys allow you to move the cursor up and down,
usually a line at a time, and left and right, usually a character at a time.
For many software packages, the arrow keys are also used to view parts of a document or
worksheet that extend past the size of the terminal screen. This is known as scrolling. The
up and down keys are used for...
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- Spring '14