Virtual/pure virtual explained

Question

What exactly does it mean if a function is defined as virtual and is that the same as pure virtual?

Answer 1

"A virtual function or virtual method is a function or method whose behavior can be overridden within an inheriting class by a function with the same signature" - wikipedia

This is not a good explanation for virtual functions. Because, even if a member is not virtual, inheriting classes can override it. You can try and see it yourself.

The difference shows itself when a function take a base class as a parameter. When you give an inheriting class as the input, that function uses the base class implementation of the overriden function. However, if that function is virtual, it uses the one that is implemented in the deriving class.