China has used decimal counting method since ancient times, and some practical units of measurement also use decimal, so it is easy to produce the concept of decimal. The first person to express this concept in words was Liu Hui in Wei and Jin Dynasties. In the process of calculating pi, he used seven units, such as feet, inches, minutes, centimeters, millimeters, seconds and bumps. For the following units that suddenly become smaller, they are no longer named, and they are collectively called "micro numbers".

During the Song and Yuan Dynasties, the concept of decimal was further popularized and expressed more clearly. Yang Hui's daily arithmetic (1262) has the formula of "two Jin conversion": "Find one, interval 625; Second, abdicate 125 ",that is,116 = 0.0625; 2/ 16=0. 125。 Here, "separation" and "abdication" already mean the position of decimal point. In Qin dynasty, units are placed under the chip representing integer units. For example,-Ⅲ-Ⅱ means 13. 12 inch is the earliest decimal notation in the world.

In Europe and Islamic countries, sexagesimal of Babylon has been in a dominant position for a long time, and some classic scientific works have also adopted sexagesimal, so the concept of decimal has never been developed. /kloc-Alkasi in Central Asia in the 0/5th century (? ~ 1429) is the first person to use decimals outside China. European mathematicians didn't start to consider decimals until16th century, among which Steven (1548 ~ 1620), a Dutchman, clearly expressed the method in On Decimal System (1583). The first person to express decimals as a universal form in the world today is the German mathematician kravis (1537 ~ 16 12), who began to use decimal points as a separator between integer parts and decimal parts in his book Astral Chart (1593).