I use my laptop without the battery. Is it safe to unplug the computer when I'm not using it (to save power). Do laptops have a separate battery on the motherboard as normal destops do?
Yes it is more safe than letting the adapter left on. Unplug from AC jack would be better than just from laptop. Yes it is a small battery in many cases that can be replaced every 1 to 5 or more years. Kind of rare that they need to be replaced.
Playing to the angels
Les Paul (1915-2009)
Both laptops and desktops have a tiny battery on the mboard that is used to retain user settings in the computer's bios when the computer is not running - settings in the cmos part of the bios - at the very least the current date and time. It doesn't power anything else.