What does "integer" mean?

In math, the term "integer" refers to numbers that include the counting numbers, zero and the negative of counting numbers. Integers do not contain either a fractional or a decimal part.

An example of a set of integers is (-10, -4, -2, 0, 3, 5, 7, 9). In math, there are different types of number classifications, such as counting numbers, natural numbers, whole numbers (a category which includes positive whole numbers and zero), integers, rational numbers (including ratios or fractions), real numbers (including rational and irrational numbers) and complex numbers.

While, the mathematical symbol for the set of natural numbers is the letter N, the symbol for the set of integers is Z.