I'm -totally- new to Bitcoin..as in I just downloaded it moments ago. So let me get this straight....the bitcoin software on my computer is basically both my wallet and my bank card and there is no real established bank...and transactions are handled via 'the cloud' Im guessing in a manner similar to .torrents.....so that makes it difficult if not impossible to fake them....and I can somehow turn my bitcoins into, say real legal tender (In the US) in Paypal....or is that not so?