If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Lesson 2: Whole numbers & integers

# Whole numbers & integers

Walk through the difference between whole numbers & integers. For example, is the number -8 a whole number? Is it an integer?
First we'll learn about whole numbers, then we'll learn about integers, and we'll finish by thinking about whole numbers and integers at the same time.

## Whole numbers

Whole numbers are the numbers starting at $0$ and counting up forever:
$\left\{0,1,2,3,4,5,6,7,8,9,10,11\text{…}\right\}$
Key idea: Whole numbers don't include negative numbers, fractions, or decimals.
Is $8$ a whole number?

Is $9749$ a whole number?

Is $-5$ a whole number?

Is $9.5$ a whole number?

Is $\frac{5}{7}$ a whole number?

Sweet, let's move onto integers.

## Integers

Integers are just like whole numbers, but they also include negative numbers:
$\left\{\text{…}-5,-4,-3,-2,-1,0,1,2,3,4,5\text{…}\right\}$
Key idea: Like whole numbers, integers don't include fractions or decimals.
Is $\frac{1}{3}$ an integer?

Is $7$ an integer?

Is $-9$ an integer?

Is $8.6$ an integer?

Is $-8.6$ an integer?

Is $-947$ an integer?

Is $-\frac{1}{3}$ an integer?

Great, now that we've learned both whole numbers and integers, we're ready to classify numbers.

## Classifying numbers

What type of number is $-3$?

What type of number is $5.1$?

What type of number is $12$?

## Challenge problem

Choose the statement that best describes the relationship between whole numbers and integers.

## Want to join the conversation?

• why aren't decimals whole numbers?
• Decimals aren't whole numbers because decimals are part of wholes.
• Why are negative numbers not considered whole number, yet are considered integers? And what is the difference between a whole number and an integer? I have only just started to learn the topic, but it helps me to understand why things are how they are. I can not learn when people teach things by answering similar questions with because thats the way it is. Everything has to have reason behind it, or else its just an opinion, and can never be proven as fact. Thank you
• A integer is any number that is not either a decimal or a fraction (however, both 2.000 and 2/2 are integers because they can be simplified into non-decimal and non-fractional numbers), this includes negative numbers. A whole number is any positive number(0 through infinity) (including non-integers)
• Since 0 is whole number would it be an integer?
• That's right! All whole numbers are integers, so since 0 is a whole number, 0 is also an integer.
• so an integer is a negative whole number
• No,integers include all numbers except decimals and fractions
• okI've always found math to be a fascinating subject. There's something about the way that numbers and equations interrelate that just clicks with me. I enjoy the challenge of solving complex problems, and I appreciate the way that math can be applied to so many different areas of life. Whether you're building bridges or designing computer algorithms, a solid foundation in math is essential. Plus, there's something deeply satisfying about arriving at the correct answer after working through a tough problem. Do you enjoy math as well, or do you find it frustrating?
• This is tooooooooo eaaaaaaaaaaaaasyyyyyyyyyy
• why am I so bad at this :,(
• Don't say that! All you have to do is to practice, okay? It will help you.
• This is probably the stupidest question but... how do you define 2/2 is it a whole number? is it 2? I'm so confused.