How to turn off Apple wireless keyboard . . .

Finally I learned; You can't turn off the keyboard until you've turned off the computer. Guess it has to do with bluetooth technology. Was hard to find anything on the web about this so perhaps this post will help. Also the instruction manual is incorrect. The green light does not stay on when keyboard is on. It only blinks as you turn on or off. Finally, if you want to make sure keyboard is off, just tap the caps lock. If it doesn't light up green it is off , , ,