Have you ever wanted to quickly lock your computer?  Perhaps for privacy, perhaps it’s part of your corporate security policy or in my case, to keep my son’s fast fingers from wreaking havoc on my laptop while I’m getting him something.  If this sounds like you, then read on.
Assuming you’ve set up a password for your Windows login username, press the Windows key+ L. Immediately, the Lock Dialog will appear.
To use your computer again, you must press Ctrl+Alt+Del, enter your password, and press Enter.