Touch typing

Touch typing (also called touch type or touch keyboarding) is typing without using the sense of sight to find the keys. Specifically, a touch typist will know their location on the keyboard through muscle memory. Touch typing typically involves placing the eight fingers in a horizontal row along the middle of the keyboard (the home row) and having them reach for other keys. Both two-handed touch typing and one-handed touch typing are possible.

Frank Edward McGurrin, a court stenographer from Salt Lake City, Utah who taught typing classes, reportedly invented touch typing in 1888. On a standard keyboard for English speakers the home row keys are: "ASDF" for the left hand and "JKL;" for the right hand. The keyboard is called a QWERTY keyboard because these are the first six letters on the keyboard. Most modern computer keyboards have a raised dot or bar on the home keys for the index fingers to help touch typists maintain and rediscover the correct position on the keyboard quickly with no need to look at the keys. More recently, the ability to touch type on touchscreen phones has been made possible with the use of specialized virtual keyboard software for touch typing.

"Do you not find," he said, "that with your short sight it is a little tiring to do so much typewriting?"
"I did at first," she answered, "but now I know where the letters are without looking."

Original layouts for the first few mechanical typewriters were in alphabetical order (ABCDE etc.) but the frequent jams suffered by experienced typists forced the manufacturers to change the layout of the letters, placing keys that are often pressed in a sequence as far as possible from each other. This allows engaging the second printing bar of the typewriter before the first falls down, increasing the speed of the mechanism. Equal distribution of the load over most of fingers also increased the speed as the keys of the mechanical typewriter are more difficult to press.

The calculations for keyboard layout were based on the language being typed and this meant different keyboard layouts would be needed for each language. In English speaking countries for example the first row is QWERTY, but in French speaking countries it is AZERTY. Though mechanical typewriters are now rarely used, moves to change the layout to increase speed have been largely ignored or resisted due to familiarity with the existing layout among touch typists.

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Wikipedia