Object-oriented programming is a way to structure a program by combining the algorithms and the data that the algorithms operate on into single entities called objects. Most object-oriented languages, including C++, are class-based. A class is a definition of an object—it describes the algorithms and the data, its format, and relations to other classes. An object is a concrete instantiation of a class, that is, a variable. An object has an address, which is a location in memory. A class is a user-defined type. In general, any number of objects can be instantiated from the definition provided by the class (some classes limit the number of objects that can be created, but this is an exception, not the norm).
In C++, the ...