All integers form an integer set, which is a number ring. In the integer system, zero and positive integers are collectively called nature. - 1、-2、-3、? , n, (n is a non-zero natural number) are negative integers. Positive integers, zero integers and negative integers form an integer system. Integers exclude decimals and fractions.
Extended data
We divide integers into three categories with 0 as the boundary:
1. positive integer, that is, an integer greater than 0, such as 1, 2, 3 ... until.
2. Zero is neither a positive integer nor a negative integer, but a number between positive and negative integers.
3. Negative integers, that is, integers less than 0, such as-1, -2, -3 ... until? . (n is a positive integer)
Note: Zero and positive integers are collectively called natural numbers.
Integers can also be divided into odd and even numbers.
Positive integer:
It has been a tool for human counting since ancient times. It can be said that it is quite natural to abstract "1 cow, 2 cows" or "5 people, 6 people" into positive integers.
Zero:
Zero not only means "nothing" ("nothing"), but also is a symbol of vacancy. In ancient China, when counting chips to calculate and manipulate numbers, there was no room for counting chips. Although there is no space mark, it still creates good conditions for counting and four operations.