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On a full-size keyboard, the spacing between the keycaps for individual character keys is 0.75 inch (19 millimeters), center to center. The keycaps themselves are about 0.5 inch (12.5 millimeters) across at the top, dished to help you place your fingers. The shape of this curve is somewhat arbitrary. Most American designs put a concave cylindrical curve (it's curved only around the longitudinal axis) at the top of the keys; some European designs use a concave spherical curve.
The one unvarying aspect of keyboards also seems the most odd—the nonalphabetical arrangement of the alphabet keys. Anyone new to typing will be amazed and perplexed at the seemingly nonsensical arrangement of letters on the keys of the typical computer keyboard. Even the name given to this esoteric layout has the ring of some kind of black magic or odd cabala—QWERTY. Simply a list of the first six characters of the top row of the nominal arrangement, the absurdity harks back to the keyboard of the first practical typewriter.
There is no doubt that the standard arrangement is not the only possible ordering of the alphabet—in fact, there are 26! (or 26 factorial, exactly 403,291,461,126,605,635,584,000,000) different possible arrangements of letters alone, not to mention the further complications of using rows of different lengths and nonalphabetic keys. QWERTY is not the only possible layout, and it's probably not the best. Nor is it the worst. But it is the standard that millions of people have spent years mastering.
A legend surrounds the QWERTY key arrangement. The typewriter was invented in 1867 by Christopher Sholes, and his very first keyboard had its letter keys arranged alphabetically. Within a year of his invention, however, Sholes discovered what he viewed as a superior arrangement, QWERTY.
According to the common myth, Sholes created QWERTY because typists pounded on keys faster than the simple mechanisms of the first typewriters could handle their strokes. The keys jammed. The odd QWERTY arrangement slowed down the typists and prevented the jams.
Sholes left no record of how he came upon the QWERTY arrangement, but it certainly was not to slow down speedy typists. High typing rates imply modern-day touch typing, ten fingers flying across the keyboard. This style of typing did not arise until about ten years after Sholes had settled on the QWERTY arrangement. Typewriter development was indeed slow—the Shift key wasn't added to the basic design to permit lowercase characters until 1878!
Other hypotheses about the QWERTY placement also lead to dead-ends. For example, breaking a strict alphabetic order to separate the keys and prevent the type bars (the levers that swing up to strike letters on paper) from jamming doesn't make sense, because the arrangement of the type bars has no direct relationship to the arrangement of keys.
The most familiar challenger to QWERTY, one that crawls in a distant second in popularity and use, is the Dvorak-Dealey letter arrangement, named for its developers, August Dvorak and William L. Dealey. The name is often shortened to Dvorak. Figure 20.1 shows the Dvorak layout applied to a typical keyboard.
The Dvorak-Dealey design incorporates several ideas that should lead to faster typing. A basic goal is to foster the alteration of hands in typing. After you strike one letter with a key under a finger of your left hand, the next key you'll want to press likely is under a right-hand finger. This hand alteration is a faster typing strategy. To make hand alteration more likely, the Dvorak-Dealey arrangement places all vowels in the home row under the left hand's fingertips and the consonants used most often in the right hand's home row. Note that the Dvorak-Dealey arrangement was developed for speed and does nothing to make the keyboard more alphabetic or easier to learn to use.
The first publication of the Dvorak-Dealey keyboard was in the 1936 book Typewriting Behavior, authored by the developers of the new letter arrangement. To back up the philosophic and theoretical advantages attributed to the Dvorak-Dealey arrangement, tests were conducted in the 1930s on mechanical typewriters, amounting to typing races between the QWERTY and Dvorak-Dealey key arrangements. Dvorak and Dealey ran the tests, and—not surprisingly—they came out the winner by factors as large as 30 percent.
Dvorak believed in both his keyboard and his test results and wrote papers promoting his ideas. Alas, the more he wrote, the greater his claims became. Articles such as "There Is a Better Typewriter Keyboard" in the December 1943 issue of National Business Education Quarterly has been called by some experts "full of factual errors." Tests run by the United States Navy and the General Accounting Office reported much more modest results for Dvorak.
Notwithstanding the exaggerated claims, the Dvorak layout does offer some potential advantages in typing speed, at least after you become skilled in its use. The penalty for its increased typing throughput is increased difficulty in typing when confronted with a QWERTY keyboard.
The design of the computer makes converting to Dvorak relatively easy. Whereas typewriters have to be redesigned for the new key arrangement, you can just plug a new keyboard into your computer. Commercial Dvorak keyboards often are available by special order.
In fact, if you don't mind your keytop legend bearing no likeness to the characters that actually appear on your screen (and in your files), you can simply reprogram your computer to think that it has a Dvorak keyboard by intercepting the signals sent by the keyboard to your computer and converting them on the fly.
Windows makes specific provisions for the Dvorak key arrangement. The standard keyboard driver allows you to select the Dvorak option. From Windows Control Panel, select the Keyboard icon. Next, select the Language tab, on which you'll find a Properties button. Clicking this button will reveal a screen like that shown in Figure 20.2, one that allows you to choose the keyboard language. The Dvorak layout is available as an option in the United States layout, as shown in the figure.
Control and Function Keys
The classic key layouts fail when it comes to computer keyboards. The array of keys they offer simply doesn't match the needs of a computer control system. Certainly the alphabet hasn't changed—at least over the 125-year history of the QWERTY arrangement. But computers have needs not addressed by the letters of the alphabet or basic numerals. They require navigation keys and buttons to control system functions. Even that's not enough to provide an easy-to-use control system for applications and operating systems. In addition (as well as subtraction and other math operations), a dedicated numeric keypad can help immensely when your work involves entering a lot of numbers.
Each additional key adds another option in laying out the keyboard. Another word for it is potential chaos. Although computer manufacturers have exploited some of the opportunities to craft their own, peculiar keyboards—particularly in notebook computers—the basic design has gravitated toward a single standard.
A common design for all keyboards seems an obvious idea, but it didn't arise spontaneously. After a short, wrenching evolution between 1981 and 1987 involving three major design changes, the layout has remained subject to tinkering. The last significant change came when Microsoft added three keys tied specifically to functions in the Windows operating system. Although most keyboard-makers stick to this arrangement, they sometimes alter the size and shapes of some keys—just enough to frustrate you during your first attempts at using an unfamiliar computer.
As with QWERTY, the arrangement of auxiliary keys is quite arbitrary, to the point of defying explanation. As personal computers were emerging as a technology, the Video Data Terminal with a detached keyboard was still a relatively new concept, as were function keys. The first personal computer keyboard appeared to be designed by programmers rather than typists—it had a small Enter/Return key but placed the function keys handily left of the alphabetic keys, just a pinkie-touch away. Experienced typists—many of the early adopters of personal computers, and the most vociferous of them were writers—complained, and the engineers complied, enlarging the Enter key to make the 84-key AT keyboard (named after the 1984 IBM Personal Computer AT, which originated it).
The next wave of new users, more interested in mastering software and entering numbers, complained that the left-hand function keys didn't correspond to the help legends that sometimes appeared in a row at the bottom of the screen. As a result, in its next generation of personal computers, the Personal Systems/2 of 1987, IBM created a third design. It was one of those attempts to satisfy everyone that leaves everyone dissatisfied. To add extra features, IBM's engineers added keys, making a total of 101. Termed the Advanced Keyboard by IBM, it is also commonly called the Enhanced Keyboard. Figure 20.3 illustrates the United States layout of the Advanced Keyboard.
The key additions were several. A new, dedicated cursor control pad was provided separate from the combined numeric and cursor pad, and several other control keys were duplicated in another small pad. Two new function keys (F11 and F12) were added, and the whole dozen were moved to a top row, above and slightly separated from the alphanumeric area. Duplicate Ctrl and Alt keys were provided at either side of the spacebar, and Caps Lock was moved to the former location of the Ctrl key.
A few functions of Windows don't fall readily under the caps of 101-key keyboards. To better match the operation of Windows, many keyboard-makers now add three additional keys—two Windows keys and a pop-up menu key—in the otherwise vacant area around the spacebar, which has also shrunk to provide more room. The two Windows keys, identified by the zooming window logo on their caps, serve as attention keys to pop you into the Windows Task Manager. One is located on the left of the space bar between the Ctrl and Alt keys. The other fits on the right side, just right of the right Alt key. The third key serves to select the item at which the mouse cursor points. It is located to the right of the right Windows key.
Most makers of Windows keyboards also modify other keys for easier typing. In particular, they enlarge the Enter key to the size used by the lamented 84-key design. To provide the extra key area, the backslash shrinks and moves upward, sandwiched between a shortened Backspace key and the plus/equals key. Figure 20.4 illustrates the most common form of the 104-key Windows keyboard.
To distinguish their products and make computers easier to use, some keyboard-makers have added application pushbuttons to their keyboards that are keyed to particular software features. In most cases, these added controls take the form of round, rubberized pushbuttons in a line above the function keys. Popular Microsoft keyboards, for example, provide pushbuttons for commonly used Internet functions, such as triggering your browser forward and back as well as entering your email system.
The functions of these added buttons are defined by the keyboard driver software. The keyboard simply passes a code to your computer indicating you've pressed one of the buttons. The driver software then checks which button you've pressed and passes a predefined command along to your software. If your software differs from what Microsoft expects, the keys might not work properly. If you have installed the keyboard properly, you can adjust its settings through the Keyboard Properties menu in Windows Control Panel.
No one likes to type, except possibly masochists and men from Mars. For most people typing is a pain. In fact, extended typing without taking a break can cause pain and worse, occupational ailments such as Carpal Tunnel Syndrome. The best way to avoid such problems is to avoid typing—yet another good reason to quit early each day. When you can't avoid pounding on the keyboard all day long, the next best choice is to find a keyboard that minimizes the pain.
Human factors specialists who deal in the science of how people relate to the workplace and machines, called ergonomics, point out that the keyboard was not designed with human beings in mind. The original layout of keys in four (or five or six) rows was a mix of the arbitrary and the needs of the original lever-operated typewriter mechanism. As good as straight rows are for pounding on paper, they are an anathema for most human hands. Normal typing forces you to splay your hands apart, bending them at the wrists and keeping them in that position while you type away. The bend stresses the ligaments in your wrist and squeezes the nerves that lead into your hand through the carpal tunnel (essentially a hole in the bones of your wrist). Over time the stress adds up and may eventually impair the functioning of your hands.
Computer keyboards do not suffer the same constraints as the keyboards of mechanical typewriters. Designers can put the key switches in any position they choose. Some of the more imaginative designs result in ergonomic keyboards. These split the alphanumeric keypad in two and angle the two halves in respect to one another. The result is an odd-looking keyboard—at least to the eyes of those long used to the mechanical typewriter design—that's supposed to make typing less painful.
The theory underlying the ergonomic design is that the typing position of your hands on the split keypad lets you keep your wrists straight. Your hands follow more of the natural position they would assume when hanging down from your sides (hence the name of Microsoft's Natural Keyboard). Because there is less stress, prolonged typing should be less painful on a split-pad keyboard.
With old-fashioned keyboards, and especially those of mechanical typewriters, you must bend your wrists in another direction, vertically, for normal typing. When your arm lies flat on your desk, you must angle your hands upward to reach the keys of a keyboard lying atop your desk. When you use the little feet at the back of your keyboard to angle your keyboard further, you must bend your wrists even more.
As with the horizontal bending of your wrists, these vertical bends can also cause stress and, possibly, carpal tunnel syndrome or other occupational ailments. Consequently, many keyboards have extended wrist rests that force you to minimize the bending of your wrists.
Unlike changes to the layout of key caps, these ergonomic designs require a brief (if any) training period in which to accustom yourself to them. They might seem odd at first, but you can quickly start using them effectively. The choice of a regular or ergonomic design is simply a matter of your own preference.
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