U+C551 Hangul Syllable Alt

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The Korean alphabet, known as Hangul or Hangeul in South Korea (English: HAHN-gool; Korean: 한글; Korean pronunciation: [ha(ː)n.ɡɯɭ]) and Chosŏn'gŭl in North Korea (조선글; North Korean pronunciation [tsʰo.sʰɔn.ɡɯɭ]), is the modern writing system for the Korean language. The letters for the five basic consonants reflect the shape of the speech organs used to pronounce them. They are systematically modified to indicate phonetic features. The vowel letters are systematically modified for related sounds, making Hangul a featural writing system. It has been described as a syllabic alphabet as it combines the features of alphabetic and syllabic writing systems.

Hangul was created in 1443 CE by Sejong the Great, fourth king of the Joseon dynasty. It was an attempt to increase literacy by serving as a complement (or alternative) to the logographic Sino-Korean Hanja, which had been used by Koreans as their primary script to write the Korean language since as early as the Gojoseon period (spanning more than a thousand years and ending around 108 BCE), along with the usage of Classical Chinese.

Modern Hangul orthography uses 24 basic letters: 14 consonant letters and 10 vowel letters. There are also 27 complex letters that are formed by combining the basic letters: 5 tense consonant letters, 11 complex consonant letters, and 11 complex vowel letters. Four basic letters in the original alphabet are no longer used: 1 vowel letter and 3 consonant letters. Korean letters are written in syllabic blocks with the alphabetic letters arranged in two dimensions. For example, the South Korean city of Seoul is written as 서울, not ㅅㅓㅇㅜㄹ. The syllables begin with a consonant letter, then a vowel letter, and then potentially another consonant letter called a batchim (Korean: 받침). If the syllable begins with a vowel sound, the consonant ㅇ (ng) acts as a silent placeholder. However, when ㅇ starts a sentence or is placed after a long pause, it marks a glottal stop. Syllables may begin with basic or tense consonants but not complex ones. The vowel can be basic or complex, and the second consonant can be basic, complex or a limited number of tense consonants. How the syllable is structured depends if the baseline of the vowel symbol is horizontal or vertical. If the baseline is vertical, the first consonant and vowel are written above the second consonant (if present), but all components are written individually from top to bottom in the case of a horizontal baseline.

As in traditional Chinese and Japanese writing, as well as many other texts in East Asia, Korean texts were traditionally written top to bottom, right to left, as is occasionally still the way for stylistic purposes. However, Korean is now typically written from left to right with spaces between words serving as dividers, unlike in Japanese and Chinese. Hangul is the official writing system throughout Korea, both North and South. It is a co-official writing system in the Yanbian Korean Autonomous Prefecture and Changbai Korean Autonomous County in Jilin Province, China. Hangul has also seen limited use by speakers of the Cia-Cia language in Indonesia.