Object-Oriented Programming (OOP) is a powerful paradigm where you design your applications using classes and objects. Classes serve as blueprints, and objects are instances of those blueprints.
👉 Essential for building structured, reusable, and scalable code in larger projects.
🔹 1. What is OOP?
OOP organizes code around objects rather than just functions and data. It focuses on concepts like encapsulation, inheritance, and polymorphism to make complex systems easier to manage.
🔹 2. Class vs. Object
• Class: A blueprint or a template for creating objects. It defines the properties (attributes) and behaviors (methods) that all objects of that type will have.
• Object: An instance of a class. It's a real-world entity created from the class blueprint.
Example:
Class = Car, Object = "My blue Honda Civic"🔹 3. Defining a Class
We use the
class keyword to define a new class. Class names typically start with an uppercase letter.Syntax:
class ClassName:
# attributes (variables)
# methods (functions)
Example:
class Dog:
species = "Canis familiaris" # Class attribute
def __init__(self, name, age): # Constructor method
self.name = name # Instance attribute
self.age = age # Instance attribute
🔹 4. Creating an Object (Instantiating a Class)
To create an object from a class, you call the class name as if it were a function. This process is called instantiation.
Example:
my_dog = Dog("Buddy", 3) # Creating an object 'my_dog'
your_dog = Dog("Lucy", 5) # Creating another object 'your_dog'🔹 5. Object Attributes & Methods
• Attributes: Variables that belong to an object (e.g.,
name, age). Accessed using dot notation: object.attribute.• Methods: Functions that belong to an object (e.g.,
bark()). Defined inside the class and always take self as their first parameter.Example:
class Dog:
def __init__(self, name):
self.name = name
def bark(self): # A method
print(f"{self.name} says Woof!")
my_dog = Dog("Rex")
print(my_dog.name) # Access attribute
my_dog.bark() # Call method
Output:
RexRex says Woof!🎯 Today's Goal(What you should do)
✔️ Understand the concept of classes as blueprints and objects as instances
✔️ Define a simple class with attributes and methods
✔️ Create objects from a class