Similar to every interview there are three parts, viz., introduction about the company and the nature of business that would then transition to the interviewee's experience and job profile, secondly the candidate is grilled about the subject matter, thirdly the interviewer is interested in knowing the candidate's problem solving skills as to how does he plan to go about given his current skill sets and meet the requirements of the profile. What is terribly important here is the impression that the candidate makes on the interviewer, how does he present himself and how does he present his limited knowledge about the subject. The answers have to be clear and lack of the same creates an image of evasive personality. Only say stuff that you can back 100%. Random and irrelevant stuff would be a turn off for the interviewer.