I would like to say that the guest lecture was really helpful to all of us . That lecture help me to fine tune the object oriented concepts which i learned before in OOP lecture . And also the lecture slides given in the guest lecture was really helpful to revise what we learned so far . Some important concepts such as Abstraction , Polymorphism were explained in very practical way . I think having a lecture of experienced guest lecture like Mr Bob is a great privilege for all of us . Thank you .