An object is an instance of a class. When you declare an object, memory is allocated to it. Each object of a class has its own set of attributes (variables) of that class and can access member functions of a class. Let us declare an object of the date class:
date1 is an object of the type date.
Objects cannot access private members of a class directly.
date1.dd =10; an invalid statement
However, you can use the member functions of the same class to access private members of that class.
date1.valid (10,12); is a valid statement