Sejong the Great
One of the best works and the biggest reason why Sejong was called great was because he created the Hunminjeongeum (). It is called in modern days as Hangul (). Because of the creation of the Hunminjeongeum, Joseon (now Korea) now got its own alphabet, and many people, most of whom have never learned how to read Hanja (Chinese characters used for Korean) could learn how to read and write much more easily than before.