New short cut keys in windows 8:-

Windows logo key‌ +start typing
Search your PC
Ctrl+plus (+) or Ctrl+minus (-)
Zoom in or out of a large number of items, like apps pinned to the Start screen
Ctrl+scroll wheel
Zoom in or out of a large number of items, like apps pinned to the Start screen
Windows logo key‌ +C
Open the charms
Windows logo key‌ +F
Open the Search charm to search files
Windows logo key‌ +H
Open the Share charm
Windows logo key‌ +I
Open the Settings charm
Windows logo key‌ +J
Switch the main app and snapped app
Windows logo key‌ +K
Open the Devices charm
Windows logo key‌ +O
Lock the screen orientation (portrait or landscape)
Windows logo key‌ +Q
Open the Search charm to search apps
Windows logo key‌ +W
Open the Search charm to search settings
Windows logo key‌ +Z
Show the commands available in the app
Windows logo key‌ +spacebar
Switch input language and keyboard layout
Windows logo key‌ +Ctrl+spacebar
Change to a previously selected input
Windows logo key‌ +Tab
Cycle through open apps (except desktop apps)
Windows logo key‌ +Ctrl+Tab
Cycle through open apps (except desktop apps) and snap them as they are cycled
Windows logo key‌ +Shift+Tab
Cycle through open apps (except desktop apps) in reverse order
Windows logo key‌ +PgUp
Move the Start screen and apps to the monitor on the left (Apps in the desktop won’t change monitors)
Windows logo key‌ +PgDown
Move the Start screen and apps to the monitor on the right (apps in the desktop won’t change monitors)
Windows logo key‌ +Shift+period (.)
Snaps an app to the left
Windows logo key‌ +period (.)
Snaps an app to the right