12 hour plane layover

Just out of curiosity, for those that have traveled, when you are forced to take a super long layover in between flights...

What are your options?

Like, are you forced to stay and protect with your bags at the airport?

Or is there a place to check your bags and you can go sight see for a couple of hours and then come back?

Or do you have to take your bags with you?

Or are you not allowed to leave the airport?

Do most large airports having a napping area?

Or like what would be the normal standard options?