Today, it's natural to connect currency with coins or paper notes. However, currency has taken a number of different1throughout history. In many early societies, certain commodities (商品) became a(n) 2method of payment. The Aztecs often used cocoa beans 3trading goods directly. However, commodities have clear 4in this regard. Depending on their size, they can be hard to carry around from place to place. And in many cases, they have a(n) 5shelf life (保存期).
These are some of the reasons why minted (新发明的) currency 6. As far back as 2500 BCE, Egyptians created metal rings they used as7, and actual coins have been around since at least 700 BCE when they were used by a society in what is modern-day Turkey. Paper money didn't8until the Song Dynasty in China. Metallic money in the form of coins9from precious metals such as gold or silver has been commonplace since early civilization.
Other forms of currency that have 10include large round stones in the Pacific Islands, shells in pre-modern America, and measurements of salt.
More recently, 11has enabled a quite different form of payment: electronic currency. Using a telegraph (电报) network, Western Union completed the first 12money transfer (转让) way back in 1871. With the arrival of the computer, it became13for banks to remove money from or credit money to each other's accounts without the difficulty of14moving large sums of cash.
Today, electronic payments and digital money is not only common, but has become the most15money form.