OPTION 1
The best to shut down windows 8 is to use the Alt+F4 key combination. Simply press alt key and without releasing the alt key press F4 key and you would get a shutdown/restart prompt window like one shown below :
You can select various options like shutdown, restart, switch user, hibernate etc from the window.
OPTION 2
Other option is like shutting down the windows 7 using the start button but in slightly a different way. Press windows key to go to the home screen. Now simply click on the settings option.
After you click the settings option you would get a power button, simply click on it to get a small list menu containing the shutdown, restart and hibernate option
Those are simple steps on how you can Shutdown/Restart Windows 8
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