If you tried to pay for something with a piece of paper, you might run into some trouble.
如果你想要用一张纸来支付什么东西，你大概会遇到些麻烦。
Unless, of course, the piece of paper was a hundred dollar bill.
当然，除非你的这张纸是百元大钞。
But what is it that makes that bill so much more interesting and valuable than other pieces of paper?
可是，是什么使得这张钞票比一张纸更加有趣有价值呢？
After all, there's not much you can do with it.
毕竟它作为一张纸，并没有什么用处。
You can't eat it. You can't build things with it. And burning it is actually illegal.
它不能吃，不能用来造东西，把它烧了也是违法的。
So what's the big deal?
那又如何？
Of course, you probably know the answer.
当然，你大概知道这个问题的答案。
A hundred dollar bill is printed by the government and designated as official currency, while other pieces of paper are not.
一张百元钞票是由政府印制的，并被指定为官方货币，其他纸可不是这样。
But that's just what makes them legal.
但这只是使得这张纸合法的途径。
What makes a hundred dollar bill valuable, on the other hand, is how many or few of them are around.
另一方面，这张纸之所以有价值是因为它们数量有限。
Throughout history, most currency, including the US dollar, was linked to valuable commodities
纵观历史，大多数货币，包括美元是与有价值的商品联系在一起的，
and the amount of it in circulation depended on a government's gold or silver reserves.
而货币的流通量，取决于政府中黄金或白银的储备量。
But after the US abolished this system in 1971, the dollar became what is known as fiat money,
但自从1971年美国政府废除了黄金兑换系统后，美元从此成为了“法定货币”，
meaning not linked to any external resource but relying instead solely on government policy to decide how much currency to print.
意思是货币本身与其他东西没有关联，它的价值仅仅由政策以及发行量来决定。
So which branch of our government sets this policy?
那么是哪个政府部门来指定这种政策呢？
The Executive, the Legislative, or the Judicial?
行政部门？立法机构？还是司法机构？
The surprising answer is: none of the above!
出乎意料，它们都不是！
In fact, monetary policy is set by an independent Federal Reserve System, or the Fed,
事实上，货币政策是由独立的美国联邦储备系统指定的，它也称为美联储，
made up of 12 regional banks in major cities around the country.
这个系统由全美国内12个设立在主要城市的地区性储备银行组成。
Its board of governors, which is appointed by the president and confirmed by the Senate, reports to Congress,
储备委员会成员由总统提名，经国会参议院批准后方可上任。
and all the Fed's profit goes into the US Treasury.
美联储所有利润须转交美国财政部。
