Network question

Hi all,

I'm a newbie to Macs and am trying to learn as much as I can. I recently noticed that when you click on the Macintosh HD icon on my PowerBook, it has Network and Macintosh HD in the left hand side of the window.

My question is that I never noticed that next to Network there is an eject icon. When I click on Network, it goes to servers, and then after that it goes to blah-blah-computer.local.

Now my question is I have no idea what that is...I never noticed it before last night. Is there a way to get rid of it? Is it necessary to have? What and why is that there? Is it using up space on my hard drive?

Sorry to be such a newbie...but it's my first Mac and I don't know many Mac gurus except for those here. Please help me understand what this Network thing is.

 

Oh okie I gotcha....thank you for explaining.

Now I have another question is why would there be an eject icon there? What am I "ejecting"? I've hit that button and it's done nothing.