Four-color conjecture, also known as four-color conjecture and four-color problem, is one of the three major mathematical conjectures in the world.

The four-color conjecture that seems simple but puzzles mathematicians for nearly a century is actually a conjecture about map coloring. The main content of this conjecture is that any map can be dyed in four colors, so that the colors of adjacent countries or regions are different, and no two adjacent countries or regions are the same.

Before understanding the four-color conjecture, we need to clarify several concepts. First, let's consider a map, which consists of several countries or regions. Each country or region can be regarded as an independent region, which is connected with each other by borders. Adjacent countries or regions * * * share a border, but different countries or regions cannot * * * share a border.

The four-color conjecture is based on an intuitive feeling. In real life, when we draw a map, we usually use different colors to distinguish different countries or regions. Although we can't prove the four-color conjecture directly, we can try to prove its correctness through some methods.

Although the four-color conjecture is still an unsolved problem, it has become an important research object in mathematics. Through the in-depth study of the four-color conjecture, we can better understand the essence and characteristics of mathematical branches such as graph theory and combinatorial mathematics. At the same time, the four-color conjecture also has a wide range of practical application values, such as computer science, electronic engineering, transportation and other fields.

In a word, the four-color conjecture is a fascinating mathematical problem, which not only challenges the wisdom and ability of mathematicians, but also stimulates the public's interest and enthusiasm for mathematics. Although we have not found a complete proof method to prove the correctness of the four-color conjecture, through in-depth study of this problem, we can constantly discover new mathematical ideas and skills and promote the continuous development and progress of mathematical science.