Lesson 1: Getting Started
Lesson 2: Introduction
Lesson 3: Math
Math Basics
More Operators
More Division
Floats
Comparison Operators
Practice
Practice: Answers
Lesson 4: Strings
Lesson 5: Variables
Lesson 6: Errors
Lesson 7: Booleans
Lesson 8: Lists
Lesson 9: Logic
Lesson 10: Loops
Lesson 11: Functions
Lesson 12: Input
Lesson 13: Modules
Lesson 14: Games
Lesson 15: Minecraft
Lesson 16: Wrapping Up

Here we're learning something new about how Python works with numbers.

In Python, and in many other programming languages, a decimal number is called a **float**.

Here are some examples of decimal numbers, or floats:

When we type a math expression using division, Python gives a float back to us as a response - the answer will always be some sort of decimal number. Python uses floats by default because it wants to give us the most accurate answer possible.

>>> 10/3 3.3333333333333335 >>> 10/2 5.0

And below you can see some examples of integers - or whole numbers:

If we want Python to give us an integer instead of a float, we have to use this built-in Python function, called round(). Type the word `round`

, then inside parentheses type one of the division expressions and hit the Enter key.

>>> round(10/3) 3 >>> round(10/2) 5

Go ahead and try a few more expressions using different numbers. You might notice some new things.

The rule we've learned here is that if you want Python answers with floats - if you want to get integers, you have to use the built-in function `round()`

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Before we move on to the next thing, let's take a minute to talk about some new words you'll hear more of soon.

When we say that Python **returns** something, we're talking about the answers that Python gives us. When you type something at the prompt and hit Enter, you're asking Python a question. Then Python gives back, or returns, an answer to you.

We've also been using this word **expression** - you'll hear that a lot more as we go on. So far the expressions we've seen have been math problems. But expressions can be a lot more - we're also going to see some expressions that use words and other kinds of symbols.