aah! I accidently dragged the HD out of my finder sidebar, how get it back?

Hello,

I'm a noob at macs still. I accidently dragged my main HD off the sidebar in finder. You know the one that is set above the line, where all your drives are?

How do you get it back there.

Is the one on the desktop, the same one as that?

or is it a different one that has all the users?

Sorry to be a noob,
and thank you for your help in relieving this small bit of anxiety post accidental drag and drop

thank you! macs are just so much different than windows. It takes a while to figure out how to work all the preferences.

Thank you again.