Presentation Computer Keyboard
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Lecturer: Mrs. Pham Thi Yen
Group members:
To Trong Giang
Nguyen Van Toan
Lai Phu Kien
Nguyen Van Duc
Introduction
History of Keyboard
Keyboard Layout
Future Trends
Introduction
In computing, a keyboard is a typewriter-style keyboard.
Despite the development of alternative input devices, such
as the mouse, touchscreen, pen devices, character
recognition and voice recognition, the keyboard remains
the most commonly used and most versatile device used
for direct (human) input into computers.
A keyboard typically has characters engraved or printed on
the keys and each press of a key typically corresponds to a
single written symbol. However, to produce some symbols
requires pressing and holding several keys simultaneously
or in sequence. While most keyboard keys produce letters,
numbers or signs (characters), other keys or simultaneous
key presses can produce actions or computer commands.
In normal usage, the keyboard is used to type text and
numbers into a word processor, text editor or other
program. Keyboards are the only way to enter commands
on a command-line interface.
History of Keyboard
- In the 1860s, the
inventor Christopher
Sholes, a newspaper
editor living in
Milwaukee conceived the
characters arranged on the
typewriters
in order of alphabet
PC QWERTRY keyboard
- James Densmore, a business partner with Sholes
suggested separating out key characters often used to
speed up typing. After many changes and reorganization,
QWERTY keyboard style was officially born in1870
Dvorak keyboard
- By 1930, the Dvorak keyboard (by August Dvorak and
William Deay design) has been released, there is
significant progress on typing speed
- At the time we prepare to switch to the Dvorak
keyboard, the 2nd World War broke out. So , every
keyboard manufactured agreed standard QWERTY
- Today, the QWETRY keyboard has become so
familiar to us. It not only for PC but also integrated
for laptops, mobile phone
Keyboard Layout
Alphabetic:
There are a number of different arrangements of
alphabetic, numeric, and punctuation symbols on keys.
These different keyboard layouts arise mainly because
different people need easy access to different symbols,
either because they are inputting text in different
languages, or because they need a specialized layout for
mathematics, accounting, computer programming, or
other purposes. The United States keyboard layout is
used as default in the currently most popular operating
systems: Windows, Mac OS X and Linux.
Keyboard Layout
Some different keyboard layouts:
United States keyboard layout:
Keyboard Layout
Vietnamese keyboard layout:
Keyboard Layout
Czech (QWERTZ) keyboard layout:
Keyboard Layout
Key types:
Alphanumeric:
Alphanumberic include: a-z, 0-9 and punctuation symbols.
Many of these keys will produce different symbols when
modifier keys or shift keys are pressed. The alphabetic
characters become uppercase when the shift key or Caps Lock
key is depressed. The numeric characters become symbols or
punctuation marks when the shift key is depressed.
Keyboard Layout
Modifiers:
Modifier keys are special keys that modify the normal action
of another key, when the two are pressed in combination. For
example, <Alt> + <F4> in Microsoft Windows will close the
program in an active window. In contrast, pressing just <F4>
will probably do nothing, unless assigned a specific function
in a particular program. By themselves, modifier keys usually
do nothing.
Keyboard Layout
Navigation and typing modes:
Navigation and typing modes keys include: Arrow key, Page Up and
Page Down, Home, End, Tab, Insert, Delete, Backspace key and Lock
keys (Num lock, Caps lock, Scroll lock).
System commands:
System commands keys include: Print screen (used to capture
the entire screen), Pause/Break (used (in conjunction with
Ctrl) to pause/stop program execution or display system
properties with combination Windows key + Pause/Break),
Escape (a shortcut in dialog boxes for No, Quit, Exit, Cancel,
or Abort, back out of a mistaken command) and Menu key
(used to launch a context menu instead of right mouse
button).
Future Trends
We think, in the future, keyboard can develop in two main
directions.
Firstly, that is more and more popular of the virtual
keyboard as :
-Touch keyboard : This is this is the kind of
keyboard for touch screen, smartphone, tablet…
-
- Laser keyboard: This is a new keyboard that
appears, use optical technology to identify
Second, in a near future, the keyboard
may ceased to exist. People will interact
with the device through the audio signal
or my thought
References
Wikipedia (wikipedia.org)
Thank you for listening
