A class that serves only as a base class from which classes are derived?
A class that serves only as a base class from abstract class is derived.
When creating a class, instead of writing completely new data members and member functions, the programmer can designate that the new class should inherit the members of an existing class. This existing class is called the base class, and the new class is referred to as the derived class.
An abstract class is a class that is designed to be specifically used as a base class. An abstract class contains at least one pure virtual function. The purpose of an abstract class is to provide an appropriate base class from which other classes can inherit.