SBI stands for State, Behavior and Identity. Since every 
object has the above three.
* State:         
It is just a value to the attribute of an object at a 
particular time.

* Behaviour:

It describes the actions and their reactions of that object.

* Identity:

An object has an identity that characterizes its own 
existence. The identity makes it possible to distinguish 
any object in an unambiguous way, and independently from 
its state.