And now a word about the word YANK. People here and in the UK use this word to describe Americans. Personally, I find this term mildly offensive. But people use it constantly here! So let me break it down for you. First of all, if you're Irish, then compare "yank" to the term "mick." It's just...not nice.
The offensiveness of this term probably has its origins in the fact that people in the southern US states call us northerners "yankees" or "yanks," and trust me, it's not with affection. Now, some Americans might refer to themselves as yanks, but most of us would not.
This is my public service announcement to anyone considering using the term yank to an actual yank: Reconsider it. Is it really so hard to say "American"?