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What is int in Python

Understanding Integers in Python

When you start learning programming, especially in a language like Python, one of the first concepts you'll encounter is the integer type, commonly referred to as int. But what exactly is an int? In simple terms, an int in Python represents whole numbers, both positive and negative, including zero. It's like the counting numbers we use in everyday life, but without any fractional or decimal parts.

The Basics of Integers

Think of integers as the building blocks of mathematics in programming. Just as you use whole numbers to count apples or tally scores, integers in Python are used for counting, iterating, indexing, and more. They are one of the simplest data types and are incredibly versatile.

Creating Integers

In Python, creating an integer is as straightforward as typing out a whole number. Here's a simple example:

my_integer = 10

When you run this code, the output will be:


This code snippet creates a variable named my_integer and assigns it the value of 10, which is an integer. The print() function then outputs the value of my_integer to the screen.

Operations with Integers

Integers can be used with various arithmetic operations. These include addition, subtraction, multiplication, and division. Here's how you can use them in Python:


# Adding two integers
result = 10 + 5




# Subtracting one integer from another
result = 10 - 5




# Multiplying two integers
result = 10 * 5




Division with integers can be a bit tricky. In Python, using the / operator will result in a float (a number that can have a decimal point). To get an integer result, you can use the // operator, known as integer division.

# Dividing two integers and getting a float result
result = 10 / 5

# Dividing two integers and getting an integer result
int_result = 10 // 5



Integers and Memory

In Python, integers are objects, which means they come with some overhead compared to 'raw' integers in lower-level languages like C. However, Python handles this behind the scenes, so you don't need to worry about it as a beginner. Just know that Python's integers can grow as large as the memory available, unlike in some other languages where integers have a fixed size.

Converting to Integers

Sometimes, you'll need to convert other data types into integers. This is common when you're dealing with user input or reading text from a file. You can convert a string to an integer using the int() function, provided that the string represents a valid whole number.

# Converting a string to an integer
string_number = "100"
int_number = int(string_number)



If the string does not represent a valid integer, Python will raise a ValueError.

Integers in Real Life

To help you understand integers better, let's use an analogy. Imagine you're organizing books on a shelf and you label each shelf with a number: 1, 2, 3, and so on. These labels are like integers in Python. They're simple, straightforward, and serve as identifiers. Just as you wouldn't label a shelf 2.5 (because it doesn't make sense), you wouldn't use a float when an integer is required in Python.

Common Uses of Integers

Integers are used in a variety of situations in programming. Here are a few examples:

  • Looping: When you want to repeat an action a certain number of times, you use an integer to control the loop.
# Looping 5 times using an integer
for i in range(5):


  • Indexing: Integers are used to access elements in a sequence, like a list, by their position.
# Accessing elements by index
my_list = ['apple', 'banana', 'cherry']


  • Counting: Counters in programming are often integers that keep track of how many times an event has occurred.
# Using an integer as a counter
counter = 0
counter += 1  # Increment the counter by 1




Integers in Python are a fundamental concept that you'll use in almost every program you write. They're like the trusty pencil in a mathematician's toolkit—simple, reliable, and essential for jotting down the most basic notations. As you continue on your coding journey, you'll find that these whole numbers will be your constant companions, helping you count, calculate, and control the flow of your programs.

Remember, the beauty of programming lies in the simplicity of such concepts and their power to create complex and functional applications. Integers might seem elementary at first glance, but they form the backbone of more intricate operations you'll encounter as you delve deeper into the world of programming. Keep practicing, keep experimenting, and soon you'll be manipulating integers like a seasoned pro, making them dance to the rhythm of your code!