I answered memory leak pretty well - unreferenced memory, in short. Then came the tricky one, due to lack of real-time experience in java, I answered that memory leak can never take place in java as it has its own garbage collector. And we have around 10 minutes of discussion, over this. To which interviewer finally made a comment, and I quote "If java did not have memory leak, Cognizant would not have had so many Memory Leak Maintenance Projects!". To his this line, I accepted that may be there is memory leak for practical implementations but theoretically it should not occur as java is designed this way. For the rest of the questions, the answers are easier to find.( Key is to answer :With Full Confidence and belief in your Skills).