Graph theory is a branch of mathematics, which takes graphics as the research object. A graph in graph theory is a graph composed of several given points and lines connecting the two points. This kind of figure is usually used to describe a certain relationship between some things, with points representing things and lines connecting two points indicating that there is such a relationship between two corresponding things.

In mathematics, graph theory mainly studies the properties (such as structural properties, algebraic properties, etc.) of graphs and their extended forms (such as directed graphs, hypergraphs, colored graphs, etc.). ), and the application of graph theory in other disciplines or real life.