Categorism is a mathematical theory that deals abstractly with mathematical structures and their relationships. It deals with mathematical concepts in an abstract way and formalizes these concepts into groups of "objects" and "forms". Some people jokingly call it "generalized abstract nonsense", which appears in many branches of mathematics and some fields of theoretical computer science and mathematical physics. The research category is to try to grasp the same characteristics of various related "mathematical structures" through axiomatic methods, and to link these structures through the "structure preservation function" between them. Therefore, the systematic study of category theory will allow any general conclusion of this mathematical structure to be proved by category axioms. Consider the following example: a Grp class composed of groups contains all objects with a "group structure". In order to prove the theorem about groups, we can make logical deduction from this set of axioms. For example, from axioms, it can be immediately proved that the unit element of a group is unique.