Do spiders like to sleep

I don't know if they actually sleep in the way humans sleep, but I have a large orb-weaver that has taken up residence outside my front door. It has built a beautiful orb-shaped web, (the big round ones we usually think of, when we think of spider webs), which it sits in the middle of during the evening and night hours.

When it's really cold outside, or during the day, it retreats to the soffits (underside of the eaves) above the web, and just huddles there with its legs pulled in close to its body. I'm guessing it's going through some kind of rest period. It's obviously not doing the kind of thing lizards and snakes do, when they're only active during warmer times of day. It's very inactive until evening.