This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Well, you understand that currency means money, right? Money amounts are basically numbers, usually preceded (or succeeded) by currency symbols. So the numeric value in the managed bean will be converted to a string in HTML that has a dollar sign in front of it. That's all. Nothing too complicated going on there.
By the way, the current best practice is to use currencyCode instead of currencySymbol.