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1、Unit 2,The Internet,1. What is the Internet? is a global system of interconnected computer networks. -Wikipedia 维基百科 2. What is the use of the Internet?,Free talk,Discussion: What do you often do with the Internet? Communication Information searching Entertainment E-Commerce Other services,Internet
2、surfing,Task 1: Discourse reading (Discuss & Read) Analyze the picture,“This diagram represents a wide area network or WAN.” WAN - Wide Area Network 广域网 LAN - Local Area Network 局域网,3. How does the Internet work?,The Discourse: Comparison（对比） & Contrast （对照）,This diagram represents a wide area netwo
3、rk or WAN. Two networks are linked via satellite. One network is in Barcelona and consists of a central computer and various PCs. The other LAN is in Los Angeles and contains a central computer and several clients. In Los Angeles, the computers are connected to the telephone lines by a modem. Howeve
4、r, in Barcelona, the network is linked to fibre-optic cables. The satellite receives signals from the dish aerials. Then the signals are retransmitted to workstations in Barcelona or Los Angeles. The purpose of this integrated network may be to establish communications services on a transcontinental
5、 scale. It allows large companies and institutions to exchange information over long distances.,Discussion: What do you often do with the Internet? Communication Information searching Entertainment E-Commerce Other services,Internet surfing,Advantages of the Internet,Advantages and Disadvantages of
6、the Internet,Communication Information searching Entertainment E-Commerce Other services,Task 2: Listening comprehension,A Warning About Wireless Internet,Wireless Fidelity 无线保真 fideliti,3rd-generation,The communications industry is warning computer users to guard against a new way to steal private
7、information. They say this kind of theft is increasing. Thieves are linking their computers with other computers and stealing information that can cost honest computer users a great deal of money. They are doing this by using the most modern computer communications method - Wi-Fi. Wi-Fi is a short w
8、ay of saying wireless fidelity. Wi-Fi permits computer users to link with the Internet communications system without using wires and a telephone.,A Warning About Wireless Internet,One method used by thieves to steal such information is called the “evil twin.“ Security experts say another method used
9、 by thieves is to gather information by reading a computer screen. Thieves do this in a public place. They have even used video cameras to record the information they are trying to steal. Experts say it is easy to guard against this kind of theft. They say to make sure no one can read your computer
10、screen while you are working in a public place. Other methods of protecting your information involve special computer programs. One of these is called a firewall. A firewall prevents anyone from electronically entering your computer to search for information. Some programs make your computer invisib
11、le to anyone on the Internet. Most also block any attempt to spy on your Internet activities.,One expert says more than half the computers in the United States that are used for business lack protection and could be attacked. Information theft from wi-fi connections is a problem for computer users e
12、verywhere. Most experts agree that computer users should learn how to protect their computers and information from those who would spy or steal. Industry experts say only education and good security will stop information theft.,Advantages and Disadvantages of the Internet,Communication Information s
13、earching Entertainment E-Commerce Other services,Theft of personal information,Virus threat,Junk mail / spamming,Unhealthy contents / Pornography p: ngrfi:,Addiction to the Internet,Writing,1.陈述利弊的常见句型 （详见阅读与写作） 1.1 说明优点 An advantage of is that + 句子 （.的优点是.） It has the following advantages. It does
14、us a lot of good. It benefits us quite a lot. It is beneficial to us. 1.2说明缺点 It has more disadvantages than advantages. The disadvantages outweigh its advantages. It does us much harm. It is harmful to us.,2.拓展句/ 支持句的写作方法 Example We can communicate in a fraction of second with a person who is sitti
15、ng in the other part of the world by e-mail, and MSN the instant chatting provider. We also can chat for hours with our loved ones. There are plenty messenger services in offering.,3. 列举法,WWW: World Wide Web 万维网 IP: Internet Protocol 网络传输协定 HTTP: Hypertext Transmission Protocol 超文件传输协定 BBS: Bulletin
16、 Board System （电子）公告牌系统 E-Mail: Electronic - Mail 电子邮件 FTP: File Transfer Protocol 文件传输协定,2.Abbreviations for technical terms in computer,Task 3: Vocabulary,Text A The Internet P 28 Ex I Ex II Ex IV,Assignment,Text A The Internet,Task 1: Do the following statements agree with the information given in the passage? write: TRUE if the statement agrees with the information FALSE if the statement contradicts the information NOT GIVEN if there is no inf
