If you are invited for an interview following your application for an internship or for a graduate position, it usually means that your papers are convincing, and that you are in the small group of people who are seriously considered for the position. For internships, in fact, you may be the only candidate.
Interviews can be held in person, or over the phone. They can last 15 minutes or two days.

What are they trying to find out?

It is important for the principal investigator (or the program admission committee) to establish the following:

© Sebastian Springer 2006-7. Please contact me with suggestions for improvement.