Classes & Objects

1. What is a Class?

Class ek blueprint hai jisse hum objects create karte hain. Ye attributes (variables) aur methods (functions) contain karti hai.

2. What is an Object?

Object class ka ek instance hai. Ek object apni properties aur methods ka use kar sakta hai.

3. Example: Creating a Class and Object

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

    def greet(self):
        print(f"Hello, my name is {self.name} and I am {self.age} years old.")

# Object creation
p1 = Person("Amit", 25)
p1.greet()

Output:

Hello, my name is Amit and I am 25 years old.

4. Multiple Objects

p2 = Person("Ravi", 30)
p2.greet()

p1.greet()

Output:

Hello, my name is Ravi and I am 30 years old.
Hello, my name is Amit and I am 25 years old.

5. Example with Methods and Attributes

class Circle:
    def __init__(self, radius):
        self.radius = radius

    def area(self):
        return 3.14 * self.radius ** 2

c1 = Circle(5)
print("Area:", c1.area())

Output:

Area: 78.5

Next Step

Ab hum Python intermediate topics me jaayenge, jaise OOP advanced concepts, file handling aur modules for larger projects.