Virtual Functions in C++

A virtual function is an important concept in C++ used to implement Polymorphism. It is an integral part of object-oriented programming (OOP). With the help of a virtual function, we ensure that the function of a derived class is called at run-time, even if we are calling that function through a pointer or reference of the base class.

A virtual function is a function that is declared in a base class and can be overridden in a derived class. When we access an object of a derived class using a pointer of the base class, the virtual function helps us ensure that the function of the derived class is called at run-time.

Run-time polymorphism, dynamic binding, overriding, use of the `virtual` keyword, called via a pointer or reference, and virtual destructors.

Enables run-time polymorphism, allows for overriding, reduces code duplication, and supports dynamic binding.

Performance overhead due to run-time binding, increased complexity, and potential for incorrect overriding.