What in the world does this function do? I see it in the functions.php of some themes, in other themes, it's not even there at all. Some of the themes even spell it as register_sidebars()!?
Unfortunately for me, searching this function doesn't get me any closer to finding out what this function does. What exactly does it do?? I'm interested in developing my own theme, so i need to find out what functions I do or do not use.