New Comers always feel difficult to get a suitable topic to kill time in a job interview.
Actually, you can switch the topic to some
basic concepts as the interviewer asks you
some some technical questions. For instance, if you are asked what is the cookie technique, you can explain from the HTTP protocal.

HTTP is characteristic of being stateless. Here, stateless means memoryless.
If I ask you a question and I give you an
answer but I do not remember anything about
you, our consersation is stateless. In such a case, I don't know who are as you ask me the next question!

For comparison, I gave an example for the stateful conversation.
Q: Jabber, can you tell me sth about Java2D?
A: Sorry, I don't know much about it.
Q: Do you mean you are not good at GUI?
A: Actually, I hope I have some opportunities to play with Java2D.

If our conversation was not stateful, I would not be able to give you the second answer.
(In my second answer, I used the word "Java2D").