Decimal system, humans naturally chose decimal system. Due to the anatomical characteristics of human beings, there are ten fingers in both hands, so decimal is the most commonly used system among the carry systems spontaneously adopted by humans. The idiom "few and far between" in a sense describes a simple counting scene, and when primitive humans needed to count, the first thing they thought of was to use natural chips - fingers - to count. Decimal encoding is almost the numerical value itself. Numerical values themselves are abstract concepts in mathematics. After long-term evolution, integration, selection, and elimination, the simple and comprehensive decimal counting method has become the mainstream counting method in human culture. Through basic education training, most people have mastered the decimal counting method from a young age. There are ten apples on the plate, and by counting the apples, we abstract the value of "ten". It is stored and displayed in our minds in the form of decimal encoding "10", rather than any other form. From this perspective, decimal encoding is almost like the numerical value itself. The base number of decimal is 10, and the digits are composed of 0-9. The counting rule is every ten to one