Keyboard Layout - East Asian Languages

East Asian Languages

Chinese, Japanese and Korean require special input methods, often abbreviated to CJK IMEs (Input Method Editors), due to the thousands of possible characters in these languages. Various methods have been invented to fit every possibility into a QWERTY keyboard, so East Asian keyboards are essentially the same as those in other countries. However, their input methods are considerably more complex, without one-to-one mappings between keys and characters.

In general, the range of possibilities is first narrowed down (often by entering the desired character's pronunciation). Then, if there remains more than one possibility, the desired ideogram is selected, either by typing the number before the character, or using a graphical menu to select it. The computer assists the typist by using heuristics to guess which character is most likely desired. Although this may seem painstaking, East Asian input methods are today sufficient in that, even for beginners, typing in these languages is only slightly slower than typing English.

In Japanese, the QWERTY-based JIS keyboard layout is used, and the pronunciation of each character is entered using Hepburn romanization or Kunrei-shiki romanization. There are several kana-based typing methods. See also Japanese language and computers.

Chinese has the most complex and varied input methods. Characters can either be entered by pronunciation (like Japanese and Hanja in Korean), or by structure. Most of the structural methods are very difficult to learn but extremely efficient for experienced typists, as there is no need to select characters from a menu. For detailed description, see Chinese input methods for computers.

There exist a variety of other, slower methods in which a character may be entered. If the pronunciation of a character is not known, the selection can be narrowed down by giving its component shapes, radicals, and stroke count. Also, many input systems include a "drawing pad" permitting "handwriting" of a character using a mouse. Finally, if the computer does not have CJK software installed, it may be possible to enter a character directly through its encoding number (e.g. Unicode).

In contrast to Chinese and Japanese, Korean is typed similarly to Western languages. There exist two major forms of keyboard layouts: Dubeolsik (두벌식), and Sebeolsik (세벌식). Dubeolsik, which shares its symbol layout with the QWERTY keyboard, is much more commonly used. While Korean consonants and vowels (jamo) are grouped together into syllabic grids when written, the script is essentially alphabetical, and therefore typing in Korean is quite simple for those who understand the Korean alphabet Hangul. Each jamo is assigned to a single key. As the user types letters, the computer automatically groups them into syllabic characters. Given a sequence of jamo, there is only one unambiguous way letters can be validly grouped into syllables, so the computer groups them together as the user types.