Can I add music onto my iTunes using my iPhone?

So, I want to add music I've found on my iPhone 4 onto iTunes using only my iPhone (WITHOUT having to get the music on on iTunes on the computer first)
Is there a way?

You can connect the charger in the computer and it will backup/save anything on you iPhone. You can go to your music on the computer and there it is! (I skipped a lot of parts that I don't think is right to add) I need help explaining it.