actually, that's the international icon for power button, not just mac. If you look closer at other appliances, you will see it...
In binary terms "0" usually means off and "1" usually means on.
or you can remember it as power being cutOut or cutIn.
Blue SL with DC charge option
reserved date : 4/20/2010
order date: 9/2/2010
status: recieved 3/30/2011