ase of typing, parsing, requires that the typist break these coded blocks of information down into discrete characters. Upon parsing completion, these characters must then by translated into a specification for a particular key press. Typing's final processing operation, execution, involves implementation of these various specifications (Salthouse, 1986, p. 303).
Typing reproduces the same material as writing. Obviously, people who come to the skill already have the ability to read and write. Typing differs from writing, however, in that it reproduces symbolic material in a sequence of discrete keystrokes. The motor system must first locate a correct spatial location, then aim the appropriate finger, and finally apply sufficient force to depress a key. These actions require not only manual dexterity, they also necessitate some representation of the keyboard as a "space coordinate system."
The primary goals of most typists are speed and accuracy. The variability in speed that occurs between novice and skilled typists is usually considerable. Novices tend to use the "hunt and peck" strategy (Holding, 1989, p. 234). For the most part, this involves locating and depressing each key individually. Typical novice speeds are frequently below 10 words per minute. In contrast, professional typists generally produce words at a rate of about 60 per minute. Often, it takes such typists up to a year to acquire this ability. These professionals often read ahead as they type. As their skill increases, their finger movements become less sequential and more overlapping.
Although the basic movements involved in typing may seem relatively simple, th
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