Number Systems: Symbols?

Question

I am learning number systems in school. We need to know about "natural numbers", "whole numbers", "Integers", "rational numbers", and "irrational numbers". I already know the definitions and examples, but what I am wondering about are the symbols. What are the symbols used for these terms?

Answer 1

Counting numbers = 1, 2, 3, etc.

Whole numbers = counting numbers plus 0.

N = natural numbers = can mean either counting numbers or whole numbers. There is disagreement on the definition.

http://www.mathsisfun.com/whole-numbers.html

Z = integers = positive and negative natural numbers plus zero

Q = rational numbers = numbers that can be expressed as a fraction with an integer numerator and a non-zero natural number denominator. For example 2/3.

Irrational numbers = real numbers that cannot be expressed as a fraction with an integer numerator and a non-zero natural number denominator.

R = real numbers = all of the measuring numbers.

C = Complex numbers - I won't define those here.

We have a nested set of numbers

N ⊂ Z ⊂ Q ⊂ R ⊂ C

where each is a proper subset of the next.

http://en.wikipedia.org/wiki/Number