The math z means to represent a set of integers. A set of all integers is called an integer set. It includes all positive integers, all negative integers and zeros. In mathematics, integer sets are usually represented by z.

1, origin of integer set:

In 1920, she introduced the concepts of "left module" and "right module". The ideal theory of the whole ring written in 192 1 is a milestone in the development of commutative algebra. Among them, when Nott introduced the concept of integer ring (integer set itself is also a number ring), she was German, and the integer in German was called Zahlen, so she wrote the integer ring, and the integer set was used to represent it from then on.

2. Introduction to positive integer set:

That is, the set of all positive numbers and integers, that is, the set of natural numbers excluding 0 until infinity. Positive integer sets usually use symbols N+, N*, N 1, N >；; 0 means.

3. Introduction to Integer:

(also called integer set) includes negative integers, zero and positive integers. Integers are also called non-negative integers (0, 1, 2, 3 ...) and non-positive integers (0,-1, -2, -3 ...). Integers divisible by 2 are called even numbers. Numbers that are not divisible by 2 are called odd numbers. That is, when n is an integer, even numbers can be represented as 2n(n is an integer) and odd numbers can be represented as 2n+ 1 (or 2n- 1).

The meaning of other letters in mathematics:

1 and n represent a set of natural numbers in a set.

A non-negative integer set is a specific set, which refers to the set of all natural numbers, and is commonly represented by the symbol n. Non-negative integers include positive integers and zeros. A set of nonnegative integers is a countable set.

Q stands for a set of rational numbers.

The set of rational numbers, that is, the set of all rational numbers, is represented by the bold letter Q, and the set of rational numbers is a subset of the set of real numbers. The set of rational numbers is an infinite set with no maximum and minimum.

3.r stands for a set of real numbers.

Generally speaking, a real number set is a set that usually contains all rational numbers and irrational numbers, and is usually represented by the capital letter R.

4.N+ represents a set of positive integers.

The set of all positive integers is called a positive integer set.