Any version of Microsoft Windows
Windows Key + D
Minimizes all windows and shows desktop. Also reopens all windows.
Windows Key + E
Opens a new Windows Explorer window.
Windows Key + F
Opens a new find or search function. Typically done by clicking Start, Find or Start, Search.
Windows Key + L
Locks your workstation so no one can access your desktop without your password.
Windows Key + M
Minimizes all windows.
Windows Key + M + Shift
Reopens all minimized windows.
Shortcut Keys [continued]
Windows Key + R
Opens the run command. Typically done by clicking on Start, Run.
Alt + Tab
Switches between your open windows.