# Understand Number Sets

We’ll begin our journey by looking at the different types of numbers.

Naturally, you’re already very familiar with natural numbers which are the counting numbers like 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 … and so on to infinity.

If you add the number 0 to that set of numbers, you’ll have a set of only whole numbers.

Next, we add negative numbers. -1, -2, -3, -4, … and so on to infinity. When we add those negative numbers we have a a set of numbers called Integers.

Finally, we add fractions and any decimal number that can be written as a fraction. This one is a little harder. This number set includes all of the Integers plus fractions like 4.25 and all fractions like 4/3. This number set is known as the rational numbers set.

What about the numbers that cannot be written as fractions? These numbers are called irrational numbers. These numbers are spNecial and include numbers like Pi, e, and the square root of 2.

All together, these numbers form the set of all real numbers.

Imaginary numbers are a topic for another day.

Natural numbers – The numbers you naturally count with. All whole numbers except for “0”

Whole numbers – Numbers that have no fractions, they’re whole.

Integers – Positive and negative whole numbers.

Rational numbers – Any real number that can be written as a fraction

Irrational numbers – Crazy numbers.