Sometimes people delete the icon qhich sits on the Quick Launch bar that quickly brings them back to their desktop. If they want it back, unfortunately there is no checkbox you can check off to bring it back. But, here is how you can do it:

Copy and paste the following lines into a Notepad file.

[Shell]
Command=2
IconFile=explorer.exe,3
[Taskbar]
Command=ToggleDesktop

Save the file to your Desktop as Show Desktop.scf. Next left click on the file you just created and drag it down to the Quick Launch bar and release.