Data members are the data variables and member functions are the functions used to manipulate these variables and together these data members and member functions defines the properties and behavior o...Data members are the data variables and member functions are the functions used to manipulate these variables and together these data members and member functions defines the properties and behavior of the objects in a Class. Accessing data members and member functions: The data members and member functions of class can be accessed using the dot(‘.’) operator with the object.