the shut down buttin in the welcome screen shuts down the computer if that's what you are reffering to.
Log Off
try pressing the shut down button above the ipod . if didnt work , try holding home button and the shut down button for 5 minutes ignore everything keep pressing until it turns off .
In the top left hand corner, click on the Apple logo, and scroll down to "Shut down..." and the computer will shut down. Alternatively, you can press the power button and it should prompt you with 4 options: Restart; Sleep; Cancel; Shut Down.
You can just put it to sleep with the power button on top, or hold it down and swipe the screen to actually turn it off.
To shut off a 3rd Generation iPod Nano, hold the menu button and the middle button down for approximately 6 seconds.
If you press both the Power button and Home button simultaneously a screenshot of your current screen will be saved to your "Camera Roll". If you hold both the Power Button and Home Button your iDevice will shut down and reboot.
Push and hold the sleep button for 4 seconds, then slide the slider to the right to shut it down. * "close" in this answer was read as "shut down"
hold down the button on top of the ipod screen until something says slide to shut down then slide it across the screen.
Shutting down your Windows 8 computer can be completed in several ways. From the Windows 8 tiles screen, hover and bring up the Charms Bar, click Settings and find the Power Button OR From desktop mode, you can download free software which brings back the Start Menu button, enabling you to shut down your computer like you're used to. OR Click and hold the power button or CTRL+ALT+DEL
To reboot your android hold down the power button until it asks you if you want to shut down your device, tap yes and your device will shut down, hold down the power button again and it should turn on. Note that some device may not have the yes or no option and will shut down just by holding down the power button. Also remember to HOLD DOWN the power button instead of just pressing it.
To completely turn off an iPad, you should press the on/off button located on top of the device (at the right) for several seconds. A bar will appear on your iPad's screen with a red slide button. Slide that button to the other side, now your iPad will shut itself down
the f button!!