Iphone 4G backing up, sync, mean?

[Cheese Salsa]

Ok so my room mate and I decided to get 2 iphone 4G's yesterday (it's amazing btw!) and well, I wanted to put music on it from his computer since his computer is just overflowing with actual purchased itunes songs. So anyway, i plugged my ipod in and it suddenly says 'Sync in progress' which I am familiar with. Then Itunes says "backing up Iphone 4G" so I was like, hmm cool cool. Then I checked my Iphone and all my roommates' apps were on my fone, so I'm very confused. What does backing up mean? And along the way itunes said copying twitter, notes, etc. I have a very thorough and highly confidential notes on my Iphone, does that mean my roommates computer basically created a duplicate of my iphone contents? How come when my roommates' iphone was plugged it didn't do the same, it basically just synced and did not get any of the apps I originally have on my iphone? PLease help! I have a strong feeling that my notes are wandering on my roommates computer. HELP! THANKS IN ADVANCE!

[Kasey C]

No such thing as iPhone 4G. Perhaps you mean iPhone 4?

Each iTunes install can only be sync'ed to ONE phone.

So yes, your phone stuff was duped on your friend's phone, and vice versa.

---
Kasey C, PC guru since Apple II days
Saving is great... especially if done by your parents.

[Steve Jobs]

obviously you dont have the real itunes because nowhere in there, does it mention an iPhone 4G. there is no such thing as iPhone 4G