The scope and code system of Hangeul in relation to the concept of Hangeul gives rise to a very complex problem. Only a few years ago, different code systems of various computers for Hangeul prevented data from being exchanged among computers, but now fortunately, most of the Hangeul code systems in different computers have been unified. First, let us compare two current styles of Korean code systems: a complete Hangeul system The method of endowing each of the syllabic characters of the Korean language with its own code value.  and a system of combination Hangeul The method of combining Korean consonants and vowels which are already given their own code value. Then we will discuss their merits and demerits.

The current complete style of Hangeul codes is very difficult to accept from the standpoint of the concept of Hangeul. It consists of 2,350 syllables chosen out of all Korean syllables; 4,888 Chinese characters, and 986 special symbols, totalling 8,224 characters. It has a fatal defect in that it cannot accommodate all the Korean syllables made by normal combinations of Korean consonants and vowels. The limit on the number of syllables does not pose any problem if we only use the given 2,350 syllables and do not use any other syllables. There are, however, serious problems related to the improving or expanding of codes in the future. In the complete Hangeul system, one Korean syllable made by combinations of consonants and vowels is codified and processed as an unit independently, as with Chinese. Moreover, it is ironically assumed that it is literally a complete style so that nothing can be modified in the code system. The number of its syllables was originally restricted for the purpose of facilitating international exchange of information data. It may generally be said to have no practical problems, but from the viewpoint of Korean linguistics, it does indeed have some practical problems.

The complete Hangeul is based on the current rules for the Korean orthography and contemporary Korean vocabulary. But since the current Korean orthography and vocabulary will change with time, the code system will need to be changed to accommodate new syllables. When we have to use new syllables owing to the future changes of the current orthography, or meet a new word which has to be represented with new syllables, the code system itself will be compelled to change again for new syllables or new syllables will force their addition to the earlier code arrangement, with the result that there is no way but to use the unmatched Hangeul code.

Let's look at some Korean words as examples. /k?p + i # nanta/ is now pronounced as [k?psi # nanda] by some people these days. Another word /kk?kk?s+i/ is also pronounced as [k’?k’??hi]. If these pronunciations should be prescribed as standard Korean, the new syllables ‘k?ps’ and ‘kk??h’ will be needed for their grammatical representations. But the complete Hangeul doesn’t have such syllables, so there is no way to represent them in that style. Furthermore, it is impossible to add such syllables to the code system to match the Korean alphabetic arrangement. The word ‘k?ps’ has to be inserted between ‘k?p’ and ‘k?s’, but there is no space between them. In the same way there is no space for ‘kk?ch’ between ‘kk?ŋ’ and ‘kk?th’. If even one syllable were to be inserted between them, the values of the codes would be changed successively, which would make a completely different new code system. Changing the values of the Hangeul code would make it impossible to use a number of accumulated data without changing of the codes. The ensuing problems would be intolerable. Moreover, to use the present Hangeul code system with its unmatched arrangement would also cause intolerable problems in co-exchanging data. Therefore, it cannot be over-emphasized that the best Hangeul code system has to be chosen from a long-term perspective. In this sense, the complete Hangeul is neither proper for processing Hangeul data nor harmonious with everyday use of Hangeul. It is unfortunate that the complete style has been used as a Korean standard code system by the government. The author is worried that the Korean DOS made on the basis of the current complete style is increasing in popularity in spite of its expected failure in the near future.

The values of codes are given to the complete syllable made up of one or more consonants and a vowel, not given to each basic consonant and vowel in the complete Hangeul. Although one or more consonants and a vowel are combined into one syllable in practical usage, Hangeul is basically a phonemic writing system. Therefore, the phoneme-unit process has to be ensured for Hangeul data to be stored in computers. Of course, it is also possible to use the phoneme-unit process in the complete Hangeul. But it is less efficient than the combination style of Hangeul. If you select the syllables that have, for example, a vowel sequence ‘wa’, all corresponding syllables have to be listed in the complete style of Hangeul, but the combination style of Hangeul has only to give the code values of ‘wa’ to the computer to find all syllables which include ‘wa’. The phoneme-unit process is needed not only in the specialized field of Korean linguistics but in everyday use of the Korean language. All syllable templates do not have to be completed ones with the CV(C) structure.

Sometimes they are made up of only one medial vowel or only one final consonant, or a medial vowel with a final consonant, or a final consonant plus one whole syllable, etc. For these syllables, consonant-or-vowel codification is necessary. For example, /-nta/ in ‘kanta(=to go), onta(=to come), and unta(=to cry)…’ shows the superiority of the combination style to the complete Hangeul.