Exchanging Money. Banks in China

When you go to China, you have to change your money from Dollars to Yuan.  Most countries require an exchange.  You can do this in two to three places.  I think it can be done at the airport.  I can't remember.  It can be done at your hotel and finally there is the bank.  When you go in, you see a guard.  You have to stand in line or pull a number.  When you exchange, you need to bring your passport.  Just remember to keep up the with exchange rate, so that you will know how much you are spending in your dollar amount.  I remember seeing the totals of $100 and thinking that was a lot of money.  It ended up being $12.50 in US dollars.  But when we got the pizza, it really was around $17 dollars.  As well as the Hamburger that cost $20.  They were charging in HK.  Hong Kong has its own currency.