Understanding Numbers, Strings and Booleans in Python


As discussed in An Introduction to Learning Python Programming, a variable is like a container that stores data values.

Think of it as a label you put on a box where you can store something (like a number or text).

You can change the contents of this box at any time.

Creating Variables:

  • Python has no command for declaring a variable.
  • A variable is created the moment you first assign a value to it.
x = 5
name = "Alice"

Here, x is a variable containing the number 5, and name is a variable containing the string “Alice”.


Numbers in Python are used to store numerical values.

They can be integers (whole numbers), floating-point numbers (numbers with a decimal point), or even complex numbers.

Types of Numbers

  • Integers: Whole numbers without a decimal point. Example: 5, -3.
  • Floats: Numbers with a decimal point. Example: 3.14, -0.001.
  • Complex: Numbers with a real and imaginary part. Example: 3 + 4j.
age = 30        # An integer
temperature = -4.5  # A floating-point number

Think of integers and floats as different measuring tools.

Integers are like a ruler without fractions, measuring only in whole units.

Floats are like a digital scale that can measure down to tiny fractions.


Strings in Python are used to store textual data.

They are a sequence of characters enclosed in quotes (either single, double, or triple quotes).

greeting = "Hello, World!"
description = 'Python is fun.'

You can think of a string as a necklace made up of letters. Each letter is a bead, and when strung together, they form a message.


Boolean represents one of two values: True or False.

In Python, booleans are often the result of a condition in a comparison or logical operation.

is_adult = True
test_passed = False

Booleans are like the light switches. They can be either on (True) or off (False).

Putting It All Together

Here’s a small example that uses these concepts:

# Variables and Data Types
name = "Alice"  # String
age = 25        # Integer
temperature = 98.6  # Float
is_student = True   # Boolean

# Displaying the values
print(name)  # Outputs: Alice
print(age + 5)  # Outputs: 30 (integer operation)
print(temperature - 0.6)  # Outputs: 98.0 (float operation)
print(not is_student)  # Outputs: False (boolean operation)

In this code snippet:

  • name, age, temperature, and is_student are variables.
  • "Alice" is a string, 25 is an integer, 98.6 is a float, and True is a boolean.

Understanding these basic types will help you manipulate data effectively in Python, forming the foundation for more complex programming tasks.