Can you tell me about the key characteristics of objects in object-oriented programming?

Key characteristics of objects in object-oriented programming (OOP):

• Encapsulation — combining data (state) and methods (behavior) within a single object, as well as hiding internal implementation from the outside world.

• Inheritance — a mechanism that allows creating new classes based on existing ones, inheriting their properties and methods, which promotes code reuse.

• Polymorphism — the ability of objects of different classes to respond to the same messages (method calls) in different ways, ensuring flexibility and extensibility.

• Abstraction — highlighting the essential characteristics of an object while hiding implementation details, simplifying interaction with the object.

Example in Java:

class Animal {
    void sound() {
        System.out.println("Some sound");
    }
}

class Dog extends Animal {
    @Override
    void sound() {
        System.out.println("Bark");
    }
}

public class Main {
    public static void main(String[] args) {
        Animal myDog = new Dog();
        myDog.sound(); // Outputs "Bark" — example of polymorphism
    }
}