Three people interviewed me and switched back and forth asking about 10-15 questions. It lasted about 20 mins. Since it was for an entry level position the questions were relatively easy and focused on my experience/education and how I would handle certain situations.

Somewhat informal, and I felt very comfortable. I was asked the usual questions (why do you want to work here, etc..). I was told about the working hours and asked if the hours worked for me (day, mid or night shift).