Can you explain what attributes are in classes in Python and how they are used?

In Python, class attributes are variables that belong to the class itself, rather than to individual instances. They are used to store data shared among all objects of the class.

Attributes can be:

• Instance attributes — unique to each object, usually defined inside the __init__ method.
• Class attributes — shared among all instances, defined directly within the class body.

Example:

class Car:
    wheels = 4  # class attribute

    def __init__(self, color):
        self.color = color  # instance attribute

car1 = Car('red')
car2 = Car('blue')

print(car1.wheels)  # 4
print(car2.wheels)  # 4
print(car1.color)   # red
print(car2.color)   # blue

Class attributes are useful for storing constants or values common to all objects, while instance attributes are for data unique to each object.