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Keyboards

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Overview

A keyboard is utilized as one of the main input devices for computers. It contains an arrangement of buttons or keys, which communicates to computer software for interpretation. In fact, the earliest computer terminals already incorporated electric typewriter keyboards for inputting information. A traditional keyboard layout for Windows was introduced in 1984 and is depicted below. It consists of 101 keys including an alphanumeric keypad, function keys, cursor keypad, and a numeric keypad.[1]

US Standard Windows Keyboard Layout

On-Screen Keyboards

If a person is unable to use a physical keyboard, but is able to operate a mouse or mouse alternative, an on-screen keyboard is an available option. These virtual keyboards are software based, which include some free ones such as the Click-N-Type. They come in a variety of layouts, depending on ease of use for the operator, such as the 3 layouts shown below. Their speedy keyboard layout lessens mouse motion by a factor of over 20 times.[2]

Click-N-Type Default Keyboard Layout
Click-N-Type Quick Keyboard Layout
Click-N-Type QWERTY Keyboard Layout

Big Button Keyboards

Accuratus Monster II Early Learning Keyboard
Accuratus Monster II Early Learning Keyboard

Some users may want to have larger keys on the keyboard to reduce mistakes by assisting in the vision of the keys. These users may have motor disability hand tremor dyslexia and other related difficulties, which would benefit from use of a larger key keyboard. Some of the major large keyboard manufacturers are the BigKeys Plus Large Key Desktop Keyboard, which reduces the layout to 60 keys, but makes the keys with lettering 10 times normal size; and the Accuratus Monster II Early Learning Keyboard, which scales the entire keyboard completely.[3] These are primarily utilized by those just learning how to use a keyboard or are undergoing rehabilitation back into use of a keyboard. For many experienced low vision users, a standard keyboard may be acceptable as long as it has sensory feedback to let users orient their hand placement.

Dvorak Layout

The Dvorak Simplified Keyboard is a keyboard layout developed in 1936 by Dr. August Dvorak and Dr. William Dealey. Dvorak proponents claim the Dvorak layout uses less finger motion, increases typing rate, and reduces errors compared to the standard QWERTY keyboard.[4] This reduction in finger distance traveled was the thought proccess of allowing faster rates of typing, and also in later years, it was proved to reduce repetitive strain injuries. Certain groups of people may be able to utilize Dvorak layout keyboards better than others, which would help if their cognitive function was intact, but motor control was slow.

Dvorak Keyboard Layout

Dvorak uses concepts such as the most common letters used being on the home row, followed by the top row, and the least common being on the bottom row. Based on the development of the layout, Dvorak estimated 70% of keyboard strokes are done on the home row and only 22% on the top row and 8% on the bottom rows.

One-Handed Dvorak Layouts

During the 1960s, Dvorak applied a similar approach of minimizing distance traveled by the fingers when he designed different arrangements for using one hand. This can provide increased accessibility to single-handed users who might struggle with excessive lateral hand movement when using two-handed keyboards. The right-handed and left-handed Dvorak layouts differ from each other by being mirror images of each other. Some people use these handed Dvorak layouts to type with one hand while using a mouse with the other. The hand is intended to rest near the center of the keyboard in order to reach the entire keyboard, eliminating the need for the split ergonomic keyboard layout.[5]

Left Dvorak Keyboard Layout
Right Dvorak Keyboard Layout

Sources

  1. http://www-01.ibm.com/software/globalization/topics/keyboards/physical.html
  2. http://cnt.lakefolks.com/
  3. http://www.keyboardspecialists.co.uk/Shop/KBS/Product/2678/K-BK-AC-LC1/BigKeysPlusLargeKeyDesktopKeyboard.aspx
  4. http://www.andong.co.uk/dvorak/
  5. http://en.wikipedia.org/wiki/Dvorak_Simplified_Keyboard#One-handed_versions

External Links

Adaptive Computer Products Software, Input Devices, and Other Products

ABCD Dvorak Typing Course A simple typing course to learn how to use the Dvorak Keyboard