The SSID is the "name" of the wireless router. Many have the default names put in them by the manufacturer, such as "default," "Linksys" or "Dlink." Their owners can change the SSID to anything, like "Sam19" or "footballfan." Most owners also turn on privacy with encryption. If the one you would use has that on, you need to find out the password.
Every wireless router has an SSID, but owners can prevent it from being displayed by outside devices. So you would need to ask for the name AND the password.
Say your next-door neighbor has a wireless router and turned on encryption. If they say you can use that router you can just ask for the name and password, but it's more polite to ask the neighbor to enter their password in your machine. That way, your machine will get on the Internet, but you won't know the password and couldn't share it with another person. Passwords get spread around that way.
Since you have your own wireless router, you may need to ask the expert who installed it what the SSID is and whether it needs a password. On my laptop is a feature that I can invoke to display the wireless networks within range. That list has "bars" similar to cell phones that show how strong the signal is, and whether it has encryption (mine shows a padlock symbol). Yours should be the strongest signal, and have a name. If it doesn't show encryption, you are ready to go. Just leave the password part blank. In fact, if you have this feature, you probably can click on it and your Nook will make the connection happen.
I don't know how to start that feature on a Nook, but I bet it's in there. Try clicking (or touching) some icons that look like they could be network tools and see what they say or do.
Good luck!
