永乐大典
The encyclopedia's physical appearance differed from any other Chinese encyclopedias of the time. It was larger in size, used special paper, and was bound in a "wrapped back" (, "bao bei zhuang") style. The use of red ink for titles and authors, an ink exclusively reserved for the emperor, helped to confirm that the volumes were of royal production. Each volume was protected by a hard-cover which was wrapped in yellow silk. The encyclopedia was not arranged by subject, like other encyclopedias, but rather by ("Hongwu zhengyun"), a system in which characters are ordered phonetically/rhythmically. The use of this system helped the reader find specific entries with ease. Although book printing already existed in the Ming Dynasty, the "Yongle Encyclopedia" was exclusively handwritten. Each handwritten entry was a collection of existing literature, some of which derived from rare and delicate texts. The importance of the "Yongle Encyclopedia" was the preservation of such texts, and the vast number of subjects it covered.