What is number　什么是数字
     A number is a mathematical object used to count and measure. A notational symbol that represents a number is called a numeral but in common use, the word number can mean the abstract object, the symbol, or the word for the number. In addition to their use in counting and measuring, numerals are often used for labels (telephone numbers), for ordering (serial numbers), and for codes (e.g., ISBNs). In mathematics, the definition of number has been extended over the years to include such numbers as zero, negative numbers, rational numbers, irrational numbers, and complex numbers.
     Certain procedures that take one or more numbers as input and produce a number as output are called numerical operations. Unary operations take a single input number and produce a single output number. For example, the successor operation adds one to an integer, thus the successor of 4 is 5. Binary operations take two input numbers and produce a single output number. Examples of binary operations include addition, subtraction, multiplication, division, and exponentiation. The study of numerical operations is called arithmetic
     Some numbers traditionally have alternative words to express them, including the following:
     ·Pair, couple, brace: 2
     ·Trio: 3
     ·Dozen: 12
     ·Baker's dozen: 13
     ·Score: 20
     ·Gross: 144
     ·Ream: 480 (old measure) 500 (new measure)
     ·Great gross: 1728
     Numbers should be distinguished from numerals, the symbols used to represent numbers. Boyer showed that Egyptians created the first ciphered numeral system.[citation needed] Greeks followed by mapping their counting numbers onto Ionian and Doric alphabets. The number five can be represented by both the base ten numeral "5", by the Roman numeral and ciphered letters. Notations used to represent numbers are discussed in the article numeral systems. An important development in the history of numerals was the development of a positional system, like modern decimals, which can represent very large numbers. The Roman numerals require extra symbols for larger numbers.
     人类最早用来计数（counting）的工具是手指和脚趾，但它们只能表示20以内的数字。当数目很大时，大多数的原始人(primitive man)就用小石子来记数。渐渐地，人们又发明了打绳结来记数(count by tying knots)的方法，或者在兽皮(animal skin)、兽骨(animal bone)、树木、石头上刻画记数。中国古代是用木、竹或骨头制成的小棍来记数，称为算筹(counting rod)。这些记数方法和记数符号慢慢转变成了最早的数字符号（数码numerical code）。如今，世界各国都使用阿拉伯数字(Arabic numerals)为标准数字。
     随着数字中的奥秘(The Secret of Numbers)逐渐被揭示，从0到9，及其无限组合出来的这些看似简单枯燥的数字，也越来越引起人们的认识和重视。例如通过姓名中的数字，可以看出工作事业、婚姻感情和财运学业等方面的吉凶(good or ill luck)情况。小小的数字为何有这么大的魔力呢？

     That number meant "woman" in the secret language of American Revolutionary War spies.
     在美国革命战争间谍们的秘密语言中，这个数字的意思是"女人"。
     And you need maybe a secret word or a secret number to get in, but we say a password, it's the word that lets you pass in, so you would need a password, which of course also might be anything.
     (上网时）你可能还需要有一个秘密的单词或数字，我们称它们为"password"。有了密码你才能进入网络，你可以选任何数字字母或词汇作为你的密码。
     Because messages are encoded numbers, you could think of this problem as having the five couriers share the secret of a number.
     由于讯息已经编码成数字，你可以将这个问题想成有五名情报员要分享一个秘密数字。
     The seemingly simple numbers contain profound mystery.
     一个个看似简单的数字中蕴含着深刻的奥秘。
     The various features presented by numbers make people exclaim over the mystery of nature and express more admiration for its secret.
     数字展现的各种特点，令人在对大自然的奥秘感叹玄妙之余，更多了一份敬佩。
     It embeds a secret voice into a digital audio signal in order to communicate secretly.
     它把秘密语音嵌入到数字音频信号中实现保密通信。
     The secret of numbers is gradually discovered and attracted more and more attention.
     数字的秘密逐渐被解释并受到越来越多的关注。
     The mysterious numbers themselves belong to an extremely counting signal. It is initially remarked by the ten heavenly stems and twelve earthly branches, and then Arabic numerals are universally used around the world.
     神奇的数字本身属于一个极为简单的记数符号，中国最早用天干地支表示，后来全世界通用阿拉伯数字。
     Many people believe that the numbers can divine good or ill luck, and forecast fortune.
     很多人认为数字可以占卜吉凶，预测运势。
     Digital watermarking techniques can be used for purposes such as label, authentication, control and dada hiding etc, by embedding a secret imperceptible signal directly into the data to be protected.
     数字水印技术通过向被保护的多媒体数据中加入透明的秘密信息，来达到标识、鉴别、控制或隐藏信息等作用。
     Generally speaking, image, audio and video watermarking are comparatively similar in algorithm realization, with their redundancy and the trait of HVS (Human Video System) or HAS (Human Audio System), in which we can embed watermark. But other than the aforementioned, there is no redundancy to transfer secret info in text document.
     一般来说，图像、音频、视频等数字水印在实现算法上比较相似，主要是利用图像、音频、视频的冗余信息和HVS(Human Video System)、HAS(Human Audio System)的特点来加载水印，但是文本数字水印和前面这几种水印不同，文本中基本上不包含用于秘密信息传递的冗余信息。
Part 3　Let's Talk！　开始交流吧！
     Stiffen: Thanks for sparing time to have lunch with me, Smith. I know how busy you are.
     史蒂芬：谢谢您赶来与我共度午餐，史密斯，我知道你很忙。
     Smith: Well, you know, Steven, it is a better way to negotiate at table because the atmosphere is relaxing and can ease the tension.
     史密斯：唔，史蒂芬，饭桌上谈判是一个好办法，因为气氛轻松，能缓解压力。
     Stiffen: Smith, I have been told there is a slight problem over price.
     史蒂芬：史密斯，我听说价格上出了点小问题。
     Smith: I don't think it's a big problem. William simply told me that he didn't have the right to make a decision.
     史密斯：我并不觉得那是什么大问题。威廉只是说他没有作决定的权力。
     Stiffen: Yes, I understand. Money issues must be determined by the boss in general.
     史蒂芬：是的，我知道。可以这么说，钱的问题一向是由老板定夺。
     Smith: I see. Don't you feel negotiating is a lot slower in this way?
     史密斯：原来如此。但你不觉得这样会使谈判进度变慢吗？
     Stiffen: Maybe short of efficiency, I admit.
     史蒂芬：我承认可能会缺乏效率。
     Smith: Well, to put it in a simple way, we feel we should be rewarded with a big discount for wholesales.
     史密斯：好吧，简单地说，我们应该享有批发的折扣。
     Stiffen: Sounds reasonable. Can you provide some numbers for me?
     史蒂芬：听起来很合理。你可否给我具体的数字呢？
     Smith: If A.J. is to be your only agent in North America, a discount of 10％ per quarter is acceptable, the more we order, the more discount we should enjoy.
     史密斯：如果A.J.日后成为贵公司在北美的独家代理商，我想每季度九折是可以接受的。订货量越多折扣也就越大。
     Stiffen: I think it is no problem, if you really feel you can sell so many.
     史蒂芬：如果你真的认为贵公司能够销售这么多的货，我想应该没问题。
     Smith: I believe so. You have got a first-class product line.
     史密斯：我相信我们办得到。因为你们有一流的生产线。
     Stiffen: I can give you the discounts if you agree to a commission of 15％ of the price.
     史蒂芬：如果你同意把佣金订为价格的百分之十五，那我就同意你要求的折扣。
     Smith: 18％ and you've got yourself a deal.
     史密斯：百分之十八，咱们成交。
     Stiffen: How about 16％?
     史蒂芬：百分之十六如何？
     Smith: OK, I think we can accept the 16％ commission.
     史密斯：好吧，可以接受净价百分之十六的佣金条件。
     Stiffen: Good. And can we agree to pay once a month?
     史蒂芬：好。我们每月付款一次可以吗？
     Smith: We'd prefer to make payment per quarter. With such large orders, it would be bad to our cash-flow if we paid out so much before sales began.
     史密斯：我想每季度付一次比较好。由于我们下的订单这么大，在进账之前就要付出这么大笔的款项将有损我们的现金流量。