Daniel Kurt 2016年8月1日
無論我們拿出紙幣或者刷信用卡，我們參與的大多數日常交易都使用貨幣。事實上，貨幣是全世界經濟的命脈。
要了解文明社會一直以來使用的貨幣，用其他代替品做比較是非常有用的。假設你做鞋為生，需要購買面包養活你的家人。你支付給面包師一雙鞋獲取一定數量的面包。但是事實是，面包師不需要鞋子。這時你就非常尴尬了，除非能找到附近需要鞋子的面包師。
貨幣解決了這一問題。它提供了一種普遍的價值儲存手段，能夠輕易的被社會其他成員接受。那個不需要鞋子的面包師可能需要一張桌子。通過接收貨幣，他能出售他的商品並且獲得一個更加方便的向家具制造商的付款方式。
通常說來，貨幣使交易可以以更加快捷的速率發生，因為賣家可以更容易的找到願意與他們做生意的買家。
貨幣還有其他重大優勢。硬幣和紙幣相對更小的體積使他們更易於攜帶。設想一下一個玉米種植商隨時帶著一車玉米去買東西將是怎樣的情形。
此外，硬幣和紙幣具有儲存更長時間的優勢，這一特點是很多商品不能具備的。例如，一個依賴直接交易的農民的資產可能在幾週之後就會損壞。使用貨幣，他就能積累和儲存他的財富。
形式多樣
現在，人們很容易把貨幣與硬幣和紙幣聯系在一起。然而，貨幣在歷史上有過多種形式。在諸多早期社會中，某些大宗商品曾為支付的手段。例如在16世紀左右，阿茲特克人通常把可可豆作為貨幣代替直接貨物交易。
然而，大宗商品在這方面有明顯的缺點。由於其體積，他們很難從一個地方攜帶到另一個地方。而且在很多情況下，他們的使用壽命非常短。
這些成為了鑄造貨幣是一個重要創新的原因。早在公元前2500年，埃及人創造了當作貨幣使用的金屬環，而真實的硬幣是在公元前700年左右在土耳其開始使用的。紙幣直到唐代的中國才出現。
在近代，技術已經能支持完全不同的支付手段——電子貨幣。通過電報網絡，西聯在1871年完成了全球第一筆電子資金轉賬。隨著大型計算機的出現，使人們能夠進行借記卡和信用卡之間的轉賬，而不需要擔心使用大量現金的麻煩。
貨幣的類型
因此，到底是什麼形成了當代的美元或者日元的這種貨幣形式呢，是價值嗎？與早期使用珍貴金屬鑄造的貨幣不同，大多數當今貨幣沒有内在價值。但是它因兩個原因保留了價值。
就代表貨幣來說，每個硬幣或者紙幣都能兌換成固定數量的商品。美元在二戰之後也獲得了這一功能，當時全世界的央行都可以使用30美元和美國政府兌換一盎司黃金。
然而，出於對美國黃金供應的擔憂，尼克松總統取消了與世界各國的協議。通過放棄金本位制度，美元變成了所謂的“法定貨幣”。換句話說，它具有持有價值僅僅是因為人們相信其他人會接受它。
現在，全球大多數主要貨幣，包括歐元、英鎊和日元，都是法定貨幣。
匯率政策
由於全球貿易的本質，貿易參與方也時常需要購買外國貨幣。政府有兩個基本政策管理這一過程。第一個是提供一個固定匯率。
這裡，政府把其貨幣與一個主要貨幣進行匯率綁定，例如美元或者歐元，在兩種貨幣之間設定固定匯率。為了維持這個匯率，該國的央行需要購買或者賣出其綁定的貨幣。
設定固定匯率的主要目的是創造一個穩定的環境，尤其是一個國家的金融市場比世界其他地方更加複雜時。固定匯率能夠增加投資者的信心。
然而，固定匯率也引起了近代的一部分貨幣危機。這是有可能的，例如，央行購買本國貨幣會導致貨幣估值過高。
與固定匯率相對的是浮動匯率。浮動匯率不是事先確定外國貨幣的價格，而是市場給出需要支付的成本。美國是使用浮動匯率的主要經濟體之一。
在浮動匯率體制中，供求關系管理外國貨幣的價值。因此，貨幣數量的增加將降低貨幣的價值。而需求的增加將會增加貨幣的價值，使得貨幣更加昂貴。
雖然“強勢”貨幣具有積極作用，它也有一些缺點。假設美元對日元升值。日本商人突然需要支付更多的成本購買美國商品，而這些成本將會被轉移給消費者。這將使美國商品在海外的競争力降低。
通貨膨脹的影響
現在大多數主要經濟體都在使用法定貨幣。因為法定貨幣不與實物資產挂鈎，政府在財務困難時期可以自由的印刷更多的貨幣。這為解決問題提供了更大的靈活性，它也創造了超支的可能。
貨幣印刷太多最大的傷害是通貨膨脹。流通的貨幣越多，其價值就越低。而適當的流通數量是無害的，貨幣不受控制的貶值將會大幅度削弱消費者的購買力。
如果年通脹達到5%，假設個人儲蓄沒有獲得利息，那麼其儲蓄價值就會比一年前降低5%。自然就很難維持同樣的生活水平。
總結
不管何種形式，所有貨幣的基本目的是相同的。它通過增加市場中各種商品的數量鼓勵經濟活動。同時，它能幫助消費者儲存財富以滿足長期需要。
How Currency Works
By Daniel Kurt | Updated August 1, 2016 — 12:02 PM EDT
Whether we pull out paper bills or swipe a credit card, most of the transactions we engage in daily use currency. Indeed, money is the lifeblood of economies around the world.
To understand why civilized societies have used currency throughout history, it’s useful to compare it to the alternative. Imagine you make shoes for a living and need to buy bread to feed your family. You approach the baker and offer a pair of shoes for a specific number of loaves. But as it turns out, he doesn’t need shoes at the moment. You’re out of luck unless you can find another baker - one who happens to be short on footwear - nearby.
Money alleviates this problem. It provides a universal store of value that can be readily used by other members of society. That same baker might need a table instead of shoes. By accepting currency, he can sell his goods and have a convenient way to pay the furniture maker.
In general, transactions can happen at a much quicker pace because sellers have an easier time finding a buyer with whom they want to do business.
There are other important benefits of money too. The relatively small size of coins and dollar bills makes them relatively simple to transport. Consider a corn grower who would have to load a cart full of food every time he needed to buy something.
Additionally, coins and paper have the advantage of lasting a long time, which is something that can’t be said for all commodities. A farmer who relies on direct trade, for example, may only have a few weeks before his assets spoil. With money, she can accumulate and store her wealth.
Various Forms
Today, it’s natural to associate currency with coins or paper notes. However, money has taken a number of different forms throughout history. In many early societies, certain commodities became a standard method of payment. Around the 16th century, for example, the Aztecs often used cocoa beans instead of trading goods directly.
However, commodities have clear drawbacks in this regard. Depending on their size, they can be hard to carry around from place to place. And in many cases, they have a limited shelf life.
These are some of the reasons why minted currency was an important innovation. As far back as 2500 B.C., Egyptians created metal rings that they used as money, and actual coins have been around since at least 700 B.C. when they were used by a society in modern-day Turkey. Paper money didn’t come about until the Tang Dynasty in China, which lasted from A.D. 618-907.
More recently, technology has enabled an entirely different form of payment: electronic currency. Using a telegraph network, Western Union (NYSE:WU) completed the first electronic money transfer way back in 1871. With the advent of mainframe computers, it became possible for banks to debit or credit each others’ accounts without the hassle of moving large sums of cash.
Types of Currency
So, what exactly gives our modern forms of currency – whether it’s an American dollar or a Japanese yen – value? Unlike early coins made of precious metals, most of what’s minted today doesn’t have much intrinsic value. However, it retains its worth for one of two reasons.
In the case of “representative money,” each coin or note can be exchanged for a fixed amount of a commodity. The dollar fell into this category in the years following World War II, when central banks around the world could pay the U.S. government $35 for an ounce of gold.
However, worries about a potential run on America’s gold supply led President Nixon to cancel this agreement with countries around the world. By leaving the gold standard, the dollar became what’s referred to as “fiat money.” In other words, it holds value simply because people have faith that other parties will accept it.
Today, most of the major currencies around the world – including the euro, British pound and yen – fall into this category.
Exchange-Rate Policies
Because of the global nature of trade, parties often need to acquire foreign currencies as well. Governments have two basic policy choices when it comes to managing this process. The first is to offer a fixed exchange rate.
Here, the government pegs its own currency to one of the major world currencies, such as the American dollar or the euro, and sets a firm exchange rate between the two denominations. To preserve the local exchange rate, the nation’s central bank either buys or sells the currency to which it is pegged.
The main goal of a fixed exchange rate is to create a sense of stability, especially when a nation's financial markets are less sophisticated than those in other parts of the world. Investors gain confidence by knowing the exact amount of the pegged currency they can acquire, if they so desire.
However, fixed exchange rates have also played a part in numerous currency crises in recent history. This can happen, for instance, when the purchase of local currency by the central bank leads to its overvaluation.
The alternative to this system is letting the currency float. Instead of pre-determining the price of a foreign currency, the market dictates what the cost will be. The United States is just one of the major economies that uses a floating exchange rate.
In a floating system, the rules of supply and demand govern a foreign currency's price. Therefore, an increase in the amount of money will make the denomination cheaper for foreign investors. And an increase in demand will strengthen the currency – that is, make it more expensive.
While a “strong” currency has positive connotations, there are drawbacks. Suppose that the dollar gained value against the yen. Suddenly, Japanese businesses would have to pay more to acquire American-made goods, likely passing their costs on to consumers. This makes U.S. products less competitive in overseas markets.
The Impact of Inflation
Most of the major economies around the world now use fiat currencies. Since they’re not linked to a physical asset, governments have the freedom to print additional money in times of financial trouble. While this provides greater flexibility to address challenges, it also creates the opportunity to overspend.
The biggest hazard of printing too much money is hyperinflation. With more of the currency in circulation, each unit becomes worth less. While modest amounts of inflation are relatively harmless, uncontrolled devaluation can dramatically erode the purchasing power of consumers.
If inflation reaches 5% annually, each individual’s savings – assuming it doesn’t accrue substantial interest – is worth 5% less than it was the previous year. Naturally, it becomes harder to maintain the same standard of living.
For this reason, central banks in developed countries usually try to keep inflation under control by indirectly taking money out of circulation when the currency loses too much value.
因為這個原因，發展中國家的中央銀行通常在流通貨幣過多時減少流通從而控制通貨膨脹。
The Bottom Line
Regardless of the form it takes, all money has the same basic goals. It helps encourage economic activity by increasing the market for various goods. And it enables consumers to store wealth and therefore address long-term needs.
本文翻譯由兄弟財經提供
文章來源：http://www.investopedia.com/articles/investing/092413/how-currency-works.asp