Recruiters were at my schools career fair and I applied for an interview through our career services office. About a week later I learned I had received an interview. The night before the interview they treated us to a dinner where we could ask questions and get to know some of the employees. The on-campus interview was a single 45 min behavioral interview.
less than a week later I received an email inviting me to an on-site interview at their IT headquarters in Bartlesville. They put me in a hotel the night before and we went to dinner with some past new hires. In the morning, we met up at a small recruiting office where they served us a delicious breakfast. We split into two groups, one started their interviews and the other went on a tour of the offices and surrounding town, then switched. There was a total of three 30 min behavioral interviews throughout the morning. They were fairly easy interviews, two of the interviewers were IT people, and one was HR. Some more past new hires took us to a nice lunch while HR met with everyone we had come in contact with since the first interview (reps from all the dinners and lunches, and all the interviewers). They discussed about all of the candidates while we were at lunch. When we got back, they wished us luck and sent us home. I really liked everyone I met there, and they were all very encouraging.
Two days later, I received a phone call letting me know I would be receiving an official offer.