Okay, dopey newbie question ...

If I open X Term I seem to be looking at a different corner of the file universe than I'm seeing when I open the File Manager application. How do I "command line over" to look at, say, the default Documents or Games folder? Likewise how do I get to my external card?

I've tried a few things, and the answer is probably obvious to anyone who is well versed in the Linux file structure and the CLI, but I ain't that guy.

Thanks.