One on one in person interview with an HR representative. I was asked general questions about why I wanted to work there and what I hoped to get out of the experience. Also general questions about my resume, nothing too philosophical or especially challenging. My skills were not tested or anything like that. I was only asked questions about fit.

Was invited to meet with the PI & a couple of grad students. Everyone was extremely friendly and the interview itself was pretty lax. The whole interview lasted about 20-30 minutes; definitely come with questions, they're here to help you and make sure that this experience is as beneficial for you as it is for them!