Jeong Inji was a Korean Neo-Confucian scholar and government minister. During the reign of Sejong the Great, he was vice-minister of education.

He is perhaps best-known for having written the postscript of the Hunmin Jeongeum Haerye

Hunmin Jeongeum Haerye

Hunminjeongeum Haerye , also called the Haerye Edition of Hunminjeongeum or simply The Haerye, is a commentary on the Hunminjeongeum, the original promulgation of hangul.It was written by scholars from the Jiphyeonjeon , commissioned by King Sejong the...

, the commentary on and explanation of the Hangul

Hangul

Hangul,Pronounced or ; Korean: 한글 Hangeul/Han'gŭl or 조선글 Chosŏn'gŭl/Joseongeul the Korean alphabet, is the native alphabet of the Korean language. It is a separate script from Hanja, the logographic Chinese characters which are also sometimes used to write Korean...

 invented by Sejong in 1443. He also contributed to the Goryeo-sa, the official history of Korea, and the Yongbi Eocheon-ga.