HT5394: OS X: About Power NapLearn about OS X: About Power Nap
Currently Being ModeratedFeb 22, 2013 6:25 AM (in response to TonyP53)
Power Nap in OS X Mountain Lion lets some Mac computers stay up to date even while they’re sleeping.
To use Power Nap, your computer must use flash memory (not a hard disk or solid-state drive). When the computer goes to sleep, Power Nap activates periodically to update information. The information that’s updated depends on whether your computer is running on battery power or plugged into a power adaptor.