If you and your friends wish to share a secret, you can write it in code, and no one else will be able to read it. Codes are one way of writing in secrets. Ciphers are another. In the code each word is written as a secret code or word number. In a cipher each letter is changed.
Codes and ciphers have played an important role in the history of the word. Julius Caesar, the Roman ruler who defeated almost all the countries in Europe about 2000years ago, used a cipher when he sent secret messages to his troops. During American Revolution, George Washingtons spies used a kind of code to send him information about the enemy before his military(军事的) action. In World War 2,the American broke, or figured out, Japans most important navy codes and got enough information to destroy a powerful Japanese fleet(舰队)。
Storekeepers use codes to mark their goods. The codes show how much was paid for the goods or when they were added to the stock. Businessman use codes to hide plans from their business enemies. Sometimes personal letters or diaries are written in code. Many people enjoy figuring out codes and ciphers simply as a hobby.
In the 16th century, codes and ciphers were very popular among scientists. They wrote messages to each other in code so that no one else would learn their secrets. Geronimo Gardano, an Italian astrologer(星相家),mathematician, and doctor, invented the trellis ciphers. He took two sheets of paper and cut exactly the same holes in each one. Then he sent one sheet, which he called a trellis, to a friend and kept the other for himself. Whenever he wanted to write a message, he put his trellis, over the clean sheet of paper and wrote the secret message through the holes. Then he removed the trellis and filed the rest of the paper with words that would make sense. When his friends received it, He put his trellis over the writing and read the secret message.
Title 1.
Keys:
1. Codes and ciphers 2.In business 3. through the holes
4. meaningful information/messages 5. Purposes/Aims
6. send secret messages/information 7. informed/know/learn/aware/conscious
8.To hide plans/information/messages 9.keep secrets 10. Defeating
下一篇: 2008年高考浙江卷的英语作文
伦敦举行世界上首个女性专场拍卖会
美国人开车时做些什么?化妆?戴隐形?
关注出境游行为规范 关心国家形象
美国公司新推发光文胸 光彩生活由此开始
女人:将节食进行到底!
体坛英语资讯:Real Madrid coach Zidane doesnt believe Bale to Shanghai rumors
国内英语资讯:Chinese premier stresses streamlining approval procedures in FTZs
国际英语资讯:Trumps campaign bans Bloomberg reporters from rallies, events
调查:韩国小偷比警察“快乐”
国际英语资讯:House judiciary committee names legal experts for first impeachment hearing
体坛英语资讯:Banska Bystrica dominates Slovak premier ice-hockey league, Bratislava waits for slip-up
澳大利亚青年网上“自我拍卖”
国内英语资讯:Xi meets foreign attendees to Imperial Springs Intl Forum, calls for upholding multilatera
只为奔“金猪” 亚洲掀起一波婴儿潮
上海:情人无价 情人节有价
调查:2006年 你觉得安全吗?
国际英语资讯:Spotlight: Pakistan set for economic jumpstart under second phase of CPEC
2019年12月英语四级作文预测:考证热
情人节送她什么?性?还是漂亮衣服?
体坛英语资讯:Bencic bests Kvitova in WTA Finals Shenzhen group stage