Introduction to Variables and Data Types

Variables are used to store information, and data types define the kind of information stored in a variable.

In this lesson, you will learn how to use variables and explore the most common data types in Python.

What are Variables?

Variables are containers that store data in your program. You can think of them as labeled boxes that hold information.

For example:

name = "Alice"

Here, name is a variable, and it stores the value "Alice".

# Defining a variable
name = "Alice"
print(name)

Data Types in Python

Every variable in Python has a data type. Here are some common ones:

• Integer (int): Whole numbers (e.g., 42).
• Float (float): Decimal numbers (e.g., 3.14).
• String (str): Text (e.g., "Hello").
• Boolean (bool): True or False values.

Assigning Different Data Types

In Python, you can assign values of different data types to variables:

# Assigning different data types
age = 25
pi = 3.14
greeting = "Hi"
is_happy = True
print(age, pi, greeting, is_happy)

Type Checking

You can check the type of a variable using the type() function:

# Checking data types
x = 42
y = 3.14
z = "Hello"
print(type(x), type(y), type(z))

Dynamic Typing in Python

Python is a dynamically typed language. This means you don’t need to specify the type of a variable. Python determines it automatically based on the value assigned:

# Dynamic typing example
num = 42
print(num)
num = "Now I am a string!"
print(num)

Converting Data Types

You can convert data types in Python using functions like int(), float(), str(), etc.:

# Converting data types
x = "123"
y = int(x)
print(y, type(y))

What Did We Learn?

In this lesson, you learned:

• What variables are and how to use them in Python.
• Common data types in Python: integers, floats, strings, and booleans.
• How to check and convert data types.

Great job! Let’s move on to the next topic.