A traditional Chinese book cover in deep blue. On the left side is a vertical white title slip bordered by a double line. The slip contains vertical text in black ink. To the right edge of the image, the white threads of traditional stitched binding are visible.

Essentials of the Complete Library of the Four Treasuries, Kept at the Hall of Spreading Elegance original: "Chizao Tang Siku Quanshu Huiyao" (摛藻堂四庫全書薈要). The "Hall of Spreading Elegance" was a specific library building within the Forbidden City. The "Essentials" (Huiyao) is a prestigious, condensed version of the "Siku Quanshu"—the largest collection of books in Chinese history—intended for the Emperor's personal use.

Masters and Philosophical Works Section original: "Zi Bu" (子部); the third of the four traditional divisions of the Chinese imperial library. This category includes works on philosophy, military strategy, medicine, and "technical sciences" such as mathematics and astronomy.