What is Object Oriented Programming ?

What’s a Class ?

What’s a Object ?

What’s the relation between Classes and Objects ?

What are different properties provided by Object-oriented systems ?(Twist :- Can
you explain different properties of Object Oriented Systems?)(Twist :- What’s
difference between Association , Aggregation and Inheritance relationships?)

How can we acheive inheritance in VB.NET ?

What are abstract classes ?

What’s a Interface ?