Tuesday, May 19, 2009

QWERTY Keyboard vs Dvorak Keyboard

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The QWERTY keyboard is intentionally ineffecient and akward. this keyboard takes twice as long to learn as it should and makes us work about twenty times harder than necessary. QWERTY was invented by Christopher Latham Sholes, who designed this keyboard to slow down typists. In his day, the type bars on a typewriter hung down in sort of a basket and pivoted up to strike the paper; then they fell back into place by gravity. when two adjoining keys were struck rapidly in succession, they jammed. Sholes rearranged the keys on a typewriter keyboard to minimize such jamming; he "anti-engineered" the letter arrangement in order to make the most commonly used letter sequences awkward. by thus making it difficult for a typist to operate the machine and slowing down typing speed, Shole's QWERTY keyboard allowed early typewriters to operate with a minimum of jamming. his design was then used in the manufacture of all typewriters.

Typewriters became mechanically more efficient, and the QWERTY keyboard design was no longer necessary to prevent jamming. the search for an improved design was led by Professor August Dvorak at the University of Washington, who in 1932 used time-and-motion studies to create a much more efficient keyboard arrangment. Dvorak filmed people while they were typing and spent a decade analyzing which operations slowed them down. the Dvorak keyboard has the letters A,O,E,U,I,D,H,T,N, and S across the home row of the typewriter. Less frequently used letters were placed on the upper and lower rows of keys. about 70 percent of typing is done on the home row, 22 percent on the upper row, and 8 percent on the lower row. On the Dvorak keyboard, hte amount of work assigned to each finger is proprtionate to its skill and strength. further, Professor Dvorak engineered his keyboard so that successive keystrokes fell on alterative hands; thus, while a finger on one hand is stroking a key, a finger on the other hand can be moving into position to hit the next key. typing rhythm is thus facilitated; this hand alternation was achieved by putting the viwels (which represent 40 percent of all letters typed) on the left-hand side and the major consonants that usually accompany these vowels on the right-hand side of the keyboard.