State: The objects are said to possess state. The present state of an object is symbolized by the joint values of its attributes. Protecting the state of an object from unsuitable inspection or modification is a significant aspect of class design and we suggest the use of accessor and mutator methods to facilitate attribute integrity and protection. The design of a class is frequently an attempt to model the states of objects in real-world. Except there is a good match among the data types accessible in the language and the states to be modeled, class design might be complex. A significant principle in class design is to make sure that an object is never put into a contradictory state by responding to the message.