천자문
This book was known at the time for being revolutionary for its practicality and creativity. The two widely-used works for learning Chinese characters during his time were called "Thousand Character Classic" and "Yoo Hap". The "Thousand Character Classic" was considered very tedious and contained words that were conceptual and not suitable for daily use, while the other text "Yoo Hap" was thought to be not suitable for daily instruction. "Hunmong Jahoe" attempted to supplement these weaknesses, while combining their strengths in the breadth of content. The "Thousand Character Classic" contained 1,000 characters, while "Hunmong Jahoe" contained 3,360 characters. It also ordered the Chinese characters with relation to its meanings: Chinese characters with similar meanings were grouped together to ease the process of learning.