There are many ways in which you can lock the computer
screen. The most popular as well as the fastest way to
lock it is to use a keyboard shortcut. The keyboard
shortcut used to lock the computer screen is Win+L. A
few of us choose to utilize the mouse to lock it. And of
course many people like to use both the options.
There is another
method in which we can lock the computer screen. It is to create a
shortcut for locking the computer screen in Windows 7. You can create a
shortcut for locking the computer screen in Windows 7, XP and
Vista too. Follow these steps in order to create a shortcut for
locking the computer screen in Windows 7 as well as other editions:
Right-click on the
desktop where you would like to create the shortcut.
Point to New.
Click on Shortcut
from the menu.

Type in this text in
the shortcut textbox. (This text will work for Windows XP as well even
though the screen will be different)
rundll32.exe
user32.dll, LockWorkStation

Click on the Next
button.
Type in a name for
your shortcut.
Click on the Finish
button.
You have
successfully created a shortcut to lock your workstation. Just click on
the shortcut whenever you want to lock the computer screen.