Most positions will use a team based interview approach. You might meet with several people at once, or several individuals over the course of a long interview - or a mix. Interviews will use a lot of behavioral questions - tell me about a time you..., etc. Since alot of them are using the same form, you may get the same question multiple times.
Above all, be positive during your interview, and be willing to say where you have made a mistake in the past and learned from it. No one is perfect.
If offered a job, you'll need to get a drug screening, background check, and health screening before you can attend orientation - all of which can take 3 or 4 weeks. Some employees actually find another job in the meantime. The health screening requires you to come to the hospital twice a week for two weeks during regular business hours. Some will wait to give 2 weeks notice until they get through the first week of the health screening.