What are the formal parts of Taoist collection?

Taoist scriptures are formally divided into seven parts, namely, the so-called "three caves" and "four auxiliary". Three holes refer to the real part of the hole, the mysterious part of the hole and the sacred part of the hole. The four auxiliary departments are Taixuan Department, Taiping Department, Taiqing Department and Zhengyi Department. Each section contains a different number of books. There are about 100 kinds of books about alchemy, and they are quite scattered. For example, the inner chapter of Bao Puzi was compiled in Taiqing Department. There are many kinds of skills in the "three caves", including some books at that time, which concentrated the "multiple skills" of the cave god department.