What is the difference between method overloading and method overriding?

Method Overloading occurs when multiple methods in the same class have the same name but different parameters (different number, type, or order of parameters). It's a compile-time polymorphism.

Method Overriding occurs when a derived class provides a specific implementation of a method that is already defined in its base class. It's a runtime polymorphism.

Example:

// Method Overloading
public class Calculator
{
    // Same method name, different parameters
    public int Add(int a, int b)
    {
        return a + b;
    }
    
    public int Add(int a, int b, int c)
    {
        return a + b + c;
    }
    
    public double Add(double a, double b)
    {
        return a + b;
    }
}

// Method Overriding
public class Animal
{
    public virtual void MakeSound()
    {
        Console.WriteLine("Some generic animal sound");
    }
}

public class Dog : Animal
{
    public override void MakeSound()
    {
        Console.WriteLine("Woof!");
    }
}

public class Cat : Animal
{
    public override void MakeSound()
    {
        Console.WriteLine("Meow!");
    }
}

// Usage
var calc = new Calculator();
calc.Add(5, 10);        // Calls first method
calc.Add(5, 10, 15);    // Calls second method

Animal myDog = new Dog();
myDog.MakeSound();      // Outputs: Woof!