I left a HO job earlier this year. The comments below about when you're "walked out" are correct--it is typically only if you are going to a competitor.
In any case, you should have your ducks in a row before giving notice. I had already taken home my personal items before giving my notice. I provided two weeks' notice and was allowed to serve out the two weeks.
You will have an exit interview on your last day. HR will ask you a few questions about why you're leaving, confirm your forwarding address for COBRA and 401k matters, and they will take your badge and company credit card. It was really a non-event.