I. History of Money
Money's got a very colourful history, because a number of things have been used in the place of what we use as money. Feathers, shells, cloth ……salt in Roman times when the Roman soldiers were paid in salt and that's how we get the word salary, from the Latin sal for salt.历史上的货币五花八门。古时候，羽毛、贝壳、布料甚至盐都曾是交换工具。古罗马士兵得到的军饷就是盐。盐这个词也是英文“工资“这个词的起源。拉丁文Sal的意思是盐，英文中工资Salary就是从它演变而来的。
And a number of tribes used cattle, which were useful because they were transportable. But they were quite bulky and you weren't always sure of the size of cattle you were going to get, so there was a problem there of quality.还有一些部落以牲畜作为交换媒介。这很有用，因为牲畜可以运来运去。但是它们体积庞大，而且无法确切知道你将要得到的牲畜的大小，因此存在质量方面的问题。
In the ninth century in China we had paper money for the first time. It wasn't quite the paper money that we know, it was more like a piece of paper saying a promise to pay.九世纪时在中国首次出现了纸币。这种纸币与我们现在使用的不同，更象是一种欠条。
And then in the seventh century we had money in the form of precious metal. There was always a problem of making sure that the coin that you got had enough precious metal in it to give it a value. When things got tough, you often found some civilisations were quite good at what they called sweating the money, which was effectively taking out the precious metal content so that what you got actually wasn't what you thought you got.另外在七世纪时出现了贵重金属货币。但如何确切知道货币中有足够的贵重金属含量以使它具有相应的价值则一直是个问题。当时局艰难时，一些文明古国会从这种货币中提取贵重金属成份，使得货币已不再拥有你原来以为它拥有的价值。
And we have a form of that here in Australia when we had the holey dollar …… when we had a coin with a hole in the middle because there was a shortage of metal.
And in those days, Spanish coins were used a lot. Sometimes stores used certain tokens because there was a shortage of actual coinage. And then there is money as we know it today in notes and coins - plastic notes.
And of course, if we were doing this program in a hundred years time we might talk about quaint little things called money, notes and coins, because all we'd be using would be plastic card.
1.precious metal 贵重金属
2.sweating the money 从货币里提取贵重金属成分
3.holey dollar 有洞的钱币，这是十九世纪在澳大利亚新南威尔士州流通的货币，因为缺乏金属材料而将钱币穿洞
5.plastic note 塑料钞票
6.plastic card （塑料）信用卡，也叫credit card