Classes

In Python, a class is a template, a prototype, a blueprint that defines the structure and behavior (attributes and methods) of objects.

So, we can say that classes are used to create objects. To create an object from a class, we need to give the object a name, set it equal to the name of the class, and then the parentheses.

computer = MyComputerClass()

Key Concepts of Classes in Python

• Class Definition: A class is defined using the class keyword followed by the class name and a colon. Class names are typically written in Pascal Case¹.

class MyClass: # this is how a class is defined

• Attributes and Methods: Attributes are variables that belong to the class. Methods are functions that belong to the class.

class MyClass:
    def my_method(self):
        message = "Hello, World!" # this is an attribute
        print(message) # this is a method

• The init Method: It is a special method called constructor that is automatically called when a new instance of the class is created; it is used to initialize the attributes of the class.

• Self Parameter: The first parameter of every method in a class, usually named self, which refers to the instance calling the method.

class MyClass:
    def __init__(self): # this is the constructor
        self.my_attribute = "Hello, World!"
        print(self.my_attribute)

• Creating an Instance: An instance is created by calling the class using its name and passing any required arguments.

my_instance = MyClass()

• Inheritance: A mechanism to create a new class using details of an existing class without modifying it. The new class (child class) inherits attributes and methods from the existing class (parent class).