The Korean alphabet is called 'Hangeul'. Each letter in Hangeul indicates an individual sound or phoneme. Hangeul is an alphabetic system and was created by King Sejong in 1443 during the Joseon Dynasty. It was originally called ‘Hunmingeongeum’ and means the ‘right sound to teach the common people’.
Before that time, Korean had an oral language but not a native alphabet, instead Chinese characters, which were sometimes modified according to the structure of Korean sounds, were used. However, it was not well suited to the structure of Korean and made writing very inconvenient.
He ruled Korea from 1418 to 1450 CE as the fourth king of the Joseon Dynasty. One of only two Korean kings called 'the Great' today, Sejong had a major impact on Korea and Koreans. His greatest achievement was creating Hangul, the Korean alphabet, but his patronage of science, technology, literature, and medicine all had a large impact on Korea and Koreans.
King Sejong conducted linguistic research to develop an alphabet that matches the structure of Korean and is easy to learn and write. The alphabet was made up of a total of 28 alphabets which consisted of 11 vowels and 17 consonants. Since that time, unused letters were removed and new letters were added, now there are 21 vowels and 19 consonants currently being used in contemporary Korean.