Virtual functions enable runtime polymorphism in C++, allowing derived classes to override base class behavior. When called via a base pointer/reference, the actual object's type determines which function is executed (dynamic dispatch). Non-virtual functions use compile-time resolution based on the pointer/reference type (static dispatch), which prevents overriding.
// Base class with virtual function
class Animal {
public:
virtual void speak() { std::cout << "Generic sound"; }
};
// Derived class override
class Dog : public Animal {
public:
void speak() override { std::cout << "Woof!"; } // Dynamic dispatch
};Visit the following resources to learn more: