The arrangement resolved the jamming problem, but it created two others. This was done so that the machine would be less likely to jam. The new layout was designed to slow down fast typists and place the keys most likely to be hit in rapid succession on opposite sides of the typewriter. In 1872 Christopher Latham Sholes (1819 –1890) developed the first typewriter, which featured the QWERTY keyboard (pronounced "kwer-tee"), so named because the first six letters near the top left of the keyboard are Q-WE-R-T-Y. Until the late nineteenth century, typewriter keys were arranged in alphabetical order. The computer keyboard is based on the layout of early typewriters. For example, when the typist presses the Caps Lock key, the keyboard encoder sends the code for the Caps Lock key to the computer, and the computer turns on the keyboard's Caps Lock light. The lights on the keyboard (for Caps Lock, Num Lock, Scroll Lock, and so on) are controlled by the computer, not the keyboard. The computer translates the scanning code into the appropriate binary code and displays the character on the monitor so that the typist can verify that the correct key was pushed. If, for example, the connection is in the first row and the third column, the encoder immediately identifies the pressed key and sends a special signal, called a "scanning code," to the computer. When the typist presses a key, a connection is made on the grid. Of signals in a grid of intersecting rows and columns. The encoder is a microprocessor located in the keyboard that detects each key as it is pressed and released. Keyboards for laptop computers have the minimum number of keys. The key set includes the standard alphanumeric keys found on old typewriters and additional keys, such as cursor keys, navigation and function keys, Apple or Windows keys, and a numeric keypad. How It WorksĪ keyboard consists of two parts: a set of keys that are pushed in sequence by the typist (or keyer) and an encoder that identifies each pressed key and generates a code that uniquely identifies that key. Keyboards can be wireless or connected to the computer by a cable. It translates each key pressed by the typist into a signal that the computer can understand. Depending on your keyboard, you may even be able to pry off the keys and rearrange them in the Dvorak layout.įor more information on keyboards and related topics, check out the links on the next page.The keyboard is the most commonly used computer input device. If you want to see for yourself, you can switch your keyboard to a Dvorak configuration just by changing a setting on your computer's operating system. This may explain why QWERTY is still the standard. An independent study in 1956 showed that QWERTY typists and Dvorak typists had about the same rate of speed, and continued studies don't show a clear winner between the two. Some argue, however, the Dvorak keyboard is no more efficient than QWERTY. If I had typed this article on a Dvorak keyboard, my fingers would have traveled 30 meters versus the 54 meters they traveled on the QWERTY keyboard I use. This site shows the layout of the Dvorak keyboard. Both "pumpkin" and "minimum" can be typed with one hand on a QWERTY keyboard - give it a try. So there are very few words in the English language that can be typed with only one hand on the Dvorak keyboard (two are "papaya" and "opaque"). The left hand has all of the vowels and some consonants and the right hand has only consonants. The Dvorak layout places all of the most commonly used letters in the home row so your fingers don't have to move at all to hit these keys. It also tries to make the typist alternate hands on consecutive letters as often as possible. The Dvorak keyboard layout tries to minimize the distance traveled by the fingers. The QWERTY keyboard is very different from the Dvorak keyboard layout. Whatever the reason for the QWERTY layout, it seems pretty unlikely that one of the first keyboard layouts invented would be perfect. So the story goes that he arranged the keys with the most common letters in hard to reach spots, to slow typists down and try to avoid this problem. ![]() Sholes' original prototypes had a problem with the bars colliding with each other and jamming.
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