The keys on a computer keyboard may be divided into basic keys and functional keys which are generally fitted on a plate. A keyboard with keys on a slope has the following disadvantages: Firstly, the action extent of the hands and arms is large when an operator works with the keyboard, and the operator will soon be fatigued with operation due to suspension of his/her wrists; secondly, only downward pressing is performed by an operator in operating a keyboard, this is disadvantageous to the memory of brain, which makes one difficult to quickly remember the exact position of the keys, as well as difficult to sufficiently exploit the potentiality of the nimbleness of the operator's fingers, and difficult to achieve blind-typing, i.e. typing without looking at the keyboard.
The keyboard is mostly used as an input device for computers, the design of a conventional English keyboard continues to use the arrangement of the QWERTY mechanical English typewriter. Many researches reveal that, from the point of view of work efficiency theory, such design of arrangement can be further improved. To improve the efficiency of inputting English with keyboard, many technical solutions of the keyboard have been put forward. The principles of man-machine efficiency theory have been taken into full consideration for keyboard improvement. In comparison with conventional keyboards, some of the improved keyboards are more adaptable to the characteristics of an operator, and exhibit significantly, increased input efficiency in laboratory experiments. These improved keyboards, however, are difficult to be popularized in practice. The main reason is that these improvements are made in the basic arrangement of keys of a conventional keyboard which has become familiar in use by generations of users who therefore prefer not to use a keyboard with a new arrangement of the keys, and furthermore, to make such improvement, the manufacturers would take a risk.