OOP and Classes

OOP and Classes

Object-oriented programming (OOP) organizes code around objects: bundles of data and behavior. Classes are the blueprints.

Class vs object

• A class is a blueprint, like a cookie cutter.
• An object is one thing made from that blueprint, like a cookie.

Classes in Python

Python supports OOP and has been object-oriented from the start. Everything is an object, even numbers and strings.

x = "hello"
print(type(x))  # <class 'str'>

Even "hello" is an object of the class str.

Create a class

class MyClass:
    x = 5

Create an object

p1 = MyClass()
print(p1.x)  # 5

The class keyword

class Name: starts a class definition. The body holds attributes and methods.

Why OOP?

• Groups related data and code.
• Reuses code through inheritance.
• Models real-world things: a Car, a User, a BankAccount.

TL;DR

• A class is a blueprint; an object is made from it.
• class Name: defines a class.
• obj = Name() creates an object.
• Everything in Python is an object.