Published in The Hankyoreh, the article explores the secrets behind premium books created by King Sejong, a passionate book enthusiast. Author Lee Jae-jung, who has researched Joseon-era metal type printing, published 'The Secret Charm of Old Books' and introduces 15 types of ancient Korean books demonstrating the evolution of Korean publishing culture from primitive origins to Joseon masterpieces. The article traces the history from the oldest Chinese books excavated in Hubei Province in 1978 through Korean wooden tablets, the Gyeongju Bulguksa Temple Stone Pagoda's Geumgang Sutra (654 AD), and the Unified Silla period handscroll 'Avatamsaka Sutra.' Particular attention is given to the evolution of bookbinding techniques, from early scroll formats to folding methods resembling folding screens, with indigo-colored Buddhist scriptures written in silver or gold ink becoming treasured art pieces of Goryeo nobility. The author especially highlights 'Zizhi Tongjian Gangmu Shizheng Quanxun Yi,' published during King Sejong's reign, emphasizing that precise grid-based character arrangement predates paper books. These books, reflecting Sejong's editorial vision and philosophy, represent the pinnacle of Korean publishing culture, proving that books transcend mere information delivery to become cultural heritage imbued with dedication and philosophy.