The World Wide Web
电子商务 中英对照E-commerce Chapter2
20世纪80年代末独立 的学术和研究网络合 并成了互联网
1979年杜克大学和 北卡罗来纳大学的 一群学生和程序员 创建了用户新闻网
20世纪90年代起 互联网成为全球 性的共享资源
1991年美国科学基金 会进一步放宽对互联 网商业活动的限制， 并对互联网实施私有 化
1996年发展到 30多万台计算 机
20世纪60年代初，美 国防部担心核武器攻 击计算机设施，意欲 创建全球性网络
1969年美国防部将加州 大学洛杉矶分校与圣巴 巴拉分校、斯坦福大学 国际研究所、犹他大学 的四台计算机连接起来
1972年 电子邮件诞 生
互 联 网 的 起 源 与 发 展
1989年美科学基金会 允许两家商业性的电 子邮件服务商与互联 网建立有限的连接
world wide web
Computer network 计算机网络 Technology allowing people to connect computers to each other Internet 因特网 A large system of interconnected computer (internet) spanning the globe(地球) World Wide Web 万维网
p58
2. Packet-switched networks
- Works well for(适用于) telephone calls
Circuit switching 线路交换
- Does not work as well for:
Sending data across large WAN, interconnected network Circuit-switched network problem 线路交换网络的问题 • Connected circuit failure - Causes interrupted connection, data loss 中断连接，数据丢失
PPT1.1
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Your Web Pages
“Reasonable” Person Principle -When hosting a website, pages should be maintained for others to view Information on the pages should be correct and up-to-date. up-toPresenting email information on web page implies being responsive to emails by surfers. Displaying personal information on web pages not a good idea.
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Internet Service Provider ( ISP )
An ISP is any one of a number of companies that enable people not only to connect to the Internet and surf the Web but also to publish Web pages.
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The main Internet service
WWW (World Wide Web)
WWW is used for Information collection and releasing Users can manipulate the mouse to find hypertext, hypermedia document provided by all sites built on WWW servers. servers.
人教版高中英语选修计算机英语TheWorldWideWebppt课件
Other Internet Services
➢What is instant messaging (IM)?
l A real-time Internet communications service that notifies you when one or more people are online and allows you to exchange messages or files
The World Wide Web
➢What graphics formats are used on the Web?
BMP
GIF
JPEG
PNG
TIFF
The World Wide Web
➢What is animation?
Appearance of motion created by displaying a series of still images in sequence
links millions of business, government agencies, schools, and individuals.
The World Wide Web
History of the Internet
➢How did the Internet originate?
How the Internet works
➢What are ways to access the Internet?
1.ISP, Regional or National 2.OSP (AOL and MSN, for example) 3.Wireless Internet
Service Provider
高考英语物理试卷
Part I Listening Comprehension (25 points)Section A (5 points)In this section, you will hear 5 short conversations. At the end of each conversation, a question will be asked about what was said. Both the conversation and the question will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A), B), C) and D), and decide which is the best answer.1. A) He is going to have a meeting. B) He is going to have a rest.C) He is going to take a break. D) He is going to take a vacation.2. A) She has finished her homework. B) She has lost her book.C) She has found her book. D) She has finished her assignment.3. A) He doesn't like playing basketball. B) He is good at playing basketball.C) He doesn't play basketball. D) He is going to play basketball.4. A) She doesn't like tea. B) She prefers coffee to tea.C) She likes both tea and coffee. D) She prefers tea to coffee.5. A) She will go to the library. B) She will go to the bookstore.C) She will go to the cinema. D) She will go to the park.Section B (20 points)In this section, you will hear a passage three times. When the passageis read for the first time, you should listen carefully for general ideas. When the passage is read for the second time, you are required to fill in the blanks with the exact words you have just heard in the blanks provided. When the passage is read for the third time, you should check what you have written.One of the most important discoveries in physics was made by a British scientist named Michael Faraday. He was born in 1791 and died in 1867.Faraday was interested in science from a young age and became ascientist by accident. He was working as a bookbinder in a bookstore when he met a famous scientist named Humphry Davy. Davy was impressed with Faraday's curiosity and intelligence, and he encouraged him to study science.Faraday began to study chemistry and physics. He was particularly interested in electricity and magnetism. In 1821, he discovered that a current of electricity passing through a wire can create a magnetic field. This discovery led to the development of electric motors and generators. In 1831, Faraday discovered that a changing magnetic field can produce an electric current. This discovery led to the development of transformers and generators.Faraday's work had a profound impact on the field of physics. He was able to explain many of the phenomena that had been observed in electricity and magnetism. His work also laid the foundation for many of the technologies that we use today. Faraday was a remarkable scientist who made significant contributions to the field of physics.Part II Structure and Vocabulary (25 points)Section A (15 points)There are 15 sentences in this section. Each sentence has one underlined word or phrase. Choose the one from the four options that best keeps the meaning of the sentence.1. A) destroyed B) destroyed C) destroyed D) destroyed2. A) studying B) studying C) studying D) studying3. A) discovered B) discovered C) discovered D) discovered4. A) influenced B) influenced C) influenced D) influenced5. A) established B) established C) established D) established6. A) contributed B) contributed C) contributed D) contributed7. A) influenced B) influenced C) influenced D) influenced8. A) contributed B) contributed C) contributed D) contributed9. A) established B) established C) established D) established10. A) discovered B) discovered C) discovered D) discovered11. A) influenced B) influenced C) influenced D) influenced12. A) contributed B) contributed C) contributed D) contributed13. A) established B) established C) established D) established14. A) discovered B) discovered C) discovered D) discovered15. A) influenced B) influenced C) influenced D) influencedSection B (10 points)Complete the following sentences with the appropriate forms of the words given in brackets.1. The experiment (repeat) many times to ensure its accuracy.2. The scientist (discover) a new element in 1898.3. The invention of the light bulb (change) our lives forever.4. The theory of relativity (propose) by Einstein in 1905.5. The solar system (form) about 4.6 billion years ago.Part III Reading Comprehension (30 points)Section A (10 points)Read the following passage and answer the questions that follow.The World Wide Web (WWW) is a vast collection of documents and other resources, primarily text, images, and sound, stored on computers all over the world. It is accessed through the Internet. The World Wide Web is a powerful tool for communication, education, and entertainment.The World Wide Web was created by Tim Berners-Lee in 1989. He was working at CERN, the European Particle Physics Laboratory, when he cameup with the idea of a hypertext system that could be used to share information. Berners-Lee developed the HTML (Hypertext Markup Language) and HTTP (Hypertext Transfer Protocol) protocols, which are used to create and display web pages.Today, the World Wide Web is used by millions of people around the world. It has become an integral part of our daily lives. We use it to access information, communicate with others, and entertain ourselves. The World Wide Web has also had a significant impact on education and business.Questions:1. What is the World Wide Web?2. Who created the World Wide Web?3. What are two uses of the World Wide Web?4. What are the two protocols used to create and display web pages?Section B (20 points)Read the following passage and answer the questions that follow.The study of physics is essential to understanding the world around us. Physics is the science of matter and energy. It seeks to explain the fundamental laws of nature and how they affect the universe.Physics has many branches, including mechanics, thermodynamics, electromagnetism, and quantum mechanics. Each branch of physics studies a different aspect of matter and energy. Mechanics, for example, studies the motion of objects. Thermodynamics studies the transfer of heat and energy. Electromagnetism studies electric and magnetic fields. Quantum mechanics studies the behavior of particles at the atomic and subatomic levels.Physics has had a profound impact on our lives. It has led to the development of many technologies, such as electricity, computers, and medical imaging. Physics has also helped us understand the universe,from the smallest particles to the largest galaxies.Questions:1. What is the main focus of physics?2. Name three branches of physics.3. How has physics impacted our lives?4. What is the significance of physics in understanding the universe?Part IV Writing (25 points)Write an essay of about 150-200 words on the following topic:How has technology changed our lives in the last 50 years?You should use your own ideas, knowledge, and experience to support your essay.Remember to:1. Write an essay in an organized manner.2. Use a variety of sentence structures.3. Use appropriate vocabulary.[Answer space provided]。
高中英语 Unit 3 The Internet Period One Listening and
Unit 3 The InternetThe Internet joins millions of computers all over the world，and today it is used by people all over the world.They think how convenient it is1 to use it.It was invented in the 1960s in the USA.The American government needed a network of computers for its army.The World Wide Web was invented by a British scientist named Tim Berners-Lee in 1989，which allowed him to send and receive scientific documents with text，drawings and photos2.In the 1990s，more and more people began to use the Internet and the World Wide Web.So what’s the difference between the Internet and the World Wide Web? The Internet is the hardware.It allows us to communicate with other people.The World Wide Web is the software.It allows us to create，see and read multimedia documents.The web is made up of millions of documents called web pages.These pages are held in computers all over the world.Many people have a favourite website with a number of web pages on the same subject3.It took 50 years for 100 million people to listen to the radio.It took 15 years for 100 million people to watch television.By the year 2000，it had taken only about three years for 100 million people to use the Internet.What will happen next on the Internet? 靓句运用于写作1．While working，I realised how hard it was to work in the fields under a hot sun.(2019·北京，书面表达) 2．First of all，I speak English fluently，which allows me to communicate with visitors without difficulty.(2019·全国Ⅰ，书面表达)3．It is just the so-called inconvenience that displays the richness，delicacy and great fascination of Chinese culture with a history of thousands of years.(2019·江苏，书面表达)Period One Listening and Speaking & Reading and Thinking—Comprehending匹配左边的单词与右边的汉语意思[第一组]1．blog A．聊天；闲聊2．engine B．方便的；近便的3．chat C．博客4．stream D．引擎；发动机5．convenient E．流播；流出；小河；溪流答案 1.C 2.D 3.A 4.E 5.B[第二组]6．cash A．软件7．update B．现金；金钱8．database C．益处；使受益；得益于9．software D．更新10．benefit E．数据库；资料库答案 6.B 7.D 8.E 9.A 10.C[第三组]11．distance A．通道；机会；进入12．inspire B．艰难的；严厉的13．access C．距离14．charity D．鼓舞；激励15．tough E．慈善；慈善机构答案11.C 12.D 13.A 14.E 15.BStep 1Fastreading1．What’s the main idea of the passage?A．People’s lives have been changed by online communities and social network. B．The Internet has separated us and made us lonely.C．The Internet can cure patients of their serious diseases.D．The Internet can help people make friends with others.答案 A2．Match each paragraph with its topic sentence.Para.1 A．Jan started an IT club and helped many other older people.Para.2 B．The Internet has made our lives more convenient.Para.3 C．Jan’s life has been improved by the Internet.Para.4 D．Jan wasn’t lonely，for the Internet removed the distance between her and others. Para.5 E．Jan has learned more about how to use the Internet to make society better. 答案Para.1 B Para.2 D Para.3 A Para.4 EPara.5 CStep 2CarefulreadingⅠ.Judge whether the following statements are true(T) or false(F)．1．There’s no doubt that the Internet has brought much convenience to people in all aspects of their life.(T)2．The Internet has removed the distance between Jan and other people，which helps her feel less lonely and bored.(T)3．Now that the 59-year-old man can’t take care of himself，his daughter can’t go to university.(F)4．Jan has started a charity website to raise money for children in poor countries.(F) 5．Jan is a kind woman and ready to help others in trouble.(T)Ⅱ.Choose the best answer.1．What convenience the Internet has brought isn’t mentioned in Para.1?A．We no longer have to wait in line or carry cash around when we go shopping.B．We can get other people’s personal information easily.C．We can get the latest information from large databases.D．We can download software，documents and images whenever we need them.答案 B2．What can we learn from the second paragraph?A．Jan has known many people online who can keep her company every day.B．After Jan was out of work，she applied for work online and found a great job. C．Jan has been good at surfing the Internet although she is old.D．Jan has started a small online company together with other two friends.答案 C3．How did the people in the online community help Jan?A．They gave her support and advice.B．They donated a lot of money to her.C．They kept her company online every day.D．They encouraged her to apply for a job.答案 A4．What does the “digital divide〞 mean?A．数字鸿沟 B．代沟C．数字差异 D．互联网距离答案 A5．Why is her next goal is to start a charity website?A．Because she thought the children in poor countries had no enough money for school. B．Because she wanted to help the children get rid of poverty.C．Because she wanted to make sure that everyone has access to the Internet. D．Because she wanted to help those who were homeless.答案 CStep 3PostreadingAfter reading the passage，please fill in the following blanks.With the development of the Internet，it has made our lives more convenient.While 1.shopping(shop)，we no 2.longer(long) have to wait in line or carry cash around.We can get the latest information and download software，documents and 3.images(image) whenever we need.At 4.the same time，online communities and social networks have also changed people’s lives and remove the distance 5.that usually exists between people.Take a woman 6.called(call) Jan Tchamani for example.She was ill 7.seriously(serious) and stuck at home,8.feeling(feel) lonely.9.However，surfing the Internet helped her know other old people and get support and advice from them.She also started an IT club 10.to help(help) other old people.Her next goal is to start a charity website to raise money for children in poor countries.Step 4Sentencelearning1．There are countless articles telling us how the Internet has made our lives more convenient.[句式分析] 本句的主干是There are countless articles；telling us how the Internet has made our lives more convenient为现在分词短语作定语，修饰articles，其中how the Internet has made our lives more convenient为宾语从句，作tell的直接宾语。
万维网带来的好处英语作文
万维网带来的好处英语作文The World Wide Web, a vast digital library, has revolutionized the way we access information. It's like having the entirety of human knowledge at our fingertips, making learning more accessible than ever before.With the click of a mouse, we can connect with people across the globe, fostering a sense of global community. This interconnectedness has broken down geographical barriers, allowing for collaboration and friendship that transcends borders.The internet has also transformed commerce, making it possible to shop from the comfort of our homes. This convenience has not only saved time but has also opened up a marketplace that is virtually limitless, offering a wide array of products and services.Moreover, the web has become a platform for self-expression, where individuals can share their thoughts, art, and ideas. This democratization of media has given a voice to the voiceless and has empowered people to participate in the global conversation.Lastly, the educational potential of the web is immense. Online courses and resources cater to every learning style and subject, allowing for personalized education that can be tailored to individual needs. This adaptability is atestament to the web's ability to adapt and evolve with the ever-changing landscape of knowledge.。
第9章 The World Wide Web
Abbreviations GML (Generalized Markup Language) 通用置标语言 SGML (Standard Generalized Markup Language) 标准通用置标语言 XML (Extensible Markup Language) 可扩展标记语言 PDA (personal digital assistant) 个人数字助理 HTML （Hypertext Markup Language ） 超文本标记语言
HTTP是每个网址的第一个字母组合，位于网址的起始位置,紧跟着它的是域名。域 名指定组织（机构）的服务器计算机，而文件收藏于服务器计算机上。大多数公司 有一个与其官方公司名字相同或接近的域名。
The directory path and document name are two more pieces of information within the Web address that help the browser track（跟 踪） down the requested page. Together, the address is called a Uniform Resource Locator, or URL. When typed into a browser, a URL tells it exactly where to look for the information.
超文本是使用嵌入式链接形成格式化网页的一种方法，这些链接将文档彼此联结， 而且将网页链接到其他对象如声音、视频或动画文件。当你点击一个图形和一个 视频剪辑播放按钮的时候，你在点击一个超链接。 clip：修剪, 夹子, 回形针, 剪下来的东西
click：单击
double-click ：双击
中考备课任务型阅读及补全对话
老李死掐中考任务型阅读任务型阅读。
它是根据任务型教学设计而成的，它是介于阅读理解与书面表达之间的一种题型。
它要求学生在阅读文章后能对文章中某些细节做到准确把握或对整篇文章进行提炼概括，是一种读写结合的题型。
这种题型既考查学生的阅读理解能力，也考查学生的分析问题、解决问题的能力，还考查学生运用英语语言将有关内容以文字形式正确地表达出来的能力。
阅读材料难度整体适中，材料后的题目设计难度并不很大，但是学生在实际做题过程中，经常会犯一些错误，导致不必要的失分。
因此我们有必要让同学们掌握一些解题方法。
★完成任务型阅读的过程就是：阅读(信息输入)→判断、分析、概括、推理(信息加工与处理)→答题(信息输出)。
具体说来，任务型阅读的解题策略包括以下四个方面：一、确阅读任务任务型阅读一般提供一段或几段阅读材料，在材料后设置3个任务，做题时我们应先阅读所给的任务，明确任务是什么，再带着任务去阅读材料，这样就能做到心中有数，有针对性地去读，并能提高阅读效率。
二、读全文，了解大意明确任务后，应迅速阅读全文来了解文章主要内容，以及文章的感情基调、作者的意图、态度倾向。
在材料后的问题设置中，最后一题对文章大意的考查。
对于概括大意的题目，需要通篇考虑，对要点加以归纳概括，这类题目有时可以从文中找到答案，但有时需要用自己的话来概括。
这类题，属于难度较大的题，对文章还得再读一读，才能总结出来。
除此之外，还经常考查“给文章拟一个标题”。
这类题目可以通过寻找主题句和高频词来完成。
根据英文写作的特点，主题句往往是首句或结尾句，但当没有主题句时，则应从全文中全面、简练地去提炼、概括。
文章的标题可以是单词、短语，也可以是句子，但不管是什么，确定标题必须遵循以下两个原则：①概括性原则,即标题应在最大程度上覆盖全文,体现文章的中心大意。
②醒目性原则，即标题必须力求吸引读者的注意力。
三、读细节，逐题攻克(一) 寻找细节，从原文中找答案在经过第二步泛读全文之后，对于材料后面问题的细节考查题，在文章中所处的大体位置有所了解。
关于网络的英语
The World Wide WebNB: This is not a word for word transcriptRob: Hello, I'm Rob.Yvonne: I'm Yvonne.Rob: And this is 6 Minute English! Today we’re celebrating a very special anniversary - the 20thanniversary of the World Wide Web.Yvonne: Ah, the World Wide Web. That’s something that's really changed our lives - and in such a short space of time.Rob: Hmm - definitely. Well, we’ll talk more about that in a moment - but first I have a question for you: on average, how long does someone spend surfing thenet each day in the UK? Is it:a) 7 minutesb) 27 minutes orc) 57 minutesYvonne: Umm – I'm going to say 27 minutes Rob, because I think people spend much more time on things like Facebook.Rob: Hmm –that's true. Well, I’ll give you the right answer at the end of the programme. But now, let’s find out more about the World Wide Web – or'www' for short.Yvonne: www –that’s an acronym! It was on Christmas Day, 20 years ago, that a breakthrough was made in the development of the internet.Rob: Yes, a breakthrough or a discovery. The man most associated with this discovery is Sir Tim Berners-Lee. He’s been nicknamed ‘The Father of theWeb’.Yvonne: What an amazing thing to invent - but of course, other people were also involved.Rob: Yes, of course. Tim Berners-Lee has been quoted as saying: “the remarkable progress of the Web today has been quite gratifying to me”. 'Gratifying' – thatreally means being satisfied - or pleased.Yvonne: Mm... so he’s rea lly pleased with what has happened to the web – and rightly so! Rob, can you tell me a bit more about his achievement?Rob: Well, Sir Tim Berners-Lee worked on the first web page in his spare time. He was a computer scientist and a computer programmer.Yvonne: And what did his groundbreaking web page say?Rob: It was just information about the project that he was working on. The webpage had a very catchy address: nxoc01.cern.ch!Yvonne: Ha ha! Yeah, really catchy!Rob: C.E.R.N spells CERN, and that’s the European Organisation for NuclearResearch, which is where he worked. But the page didn't actually go onlineuntil August 1991.Yvonne: But this really heralded the start of people communicating by computer? Rob: Yes. It really showed how computers could talk to each other using a language called Hyper Text Mark up Language.Yvonne: Ah - that’s HTML for short!Rob: Very good!Yvonne: So, HTML is the language that computers use to talk to each other – to communicate with each other.Rob: It’s very clever isn’t it?Yvonne: Hmmm.Rob: And since then the internet has evolved at a rapid rate. Now, there are believed to be around one trillion web pages.Yvonne: Whew! And I’m sure almost everyone uses the internet now – but I wonderhow we'd cope without it?Rob: Well, we've been asking people just that. Listen to what they said when we asked: how would you cope without the World Wide Web?Insert:Man:I'd just have to do without it, wouldn't I? If you remember all the scare stories of the millennium that, you know, all the power stations would shut down and all that – it didn't happen. As long as my central heating wasn't controlled by the internet, I'd just have to manage.Woman:Probably not very well. Umm - I imagine that most of my social relationships would be a lot more difficult. And also keeping in contact with people far away would also be impossible.Man:Err – with great difficulty (laughs)! It would be the phone, I imagine, and lots more writing, lots more paper. Umm – we'd need bigger file cabinets.Rob: So the first man would cope without the internet, as long as the computerswhich help provide power for his central heating – that's the system he uses tokeep warm – isn't affected! He says he'd just have to 'do without it'.Yvonne: The woman was most worried about her social relationships – keeping in contact with her friends and family.Rob: Yes, especially those who are far away. In fact, she thinks keeping in contact with them would be impossible without the internet. But the last man we heardfrom doesn't agree. Although he says he would cope with great difficulty, hedoes have some alternatives – ideas about what we could do instead.Yvonne: And he has a good point I think, Rob. We could write to each other - like we used to before we had the internet. It would be lovely to get more hand-writtenletters from friends and family rather than just e-mails, I think.Rob: That's what we call 'snail-mail'. But of course, as that man pointed out, lots more paper would mean that we'd need bigger file cabinets – the pieces offurniture that are used to keep all those bits of paper safe.Yvonne: It’s incredible how the World Wide Web has expanded in twenty years, andhow much we now rely on it. I wonder what it will be like after another twentyyears.Rob: Well, Sir Tim Berners-Lee has said: “we have only scratched the surface ofwhat could be realised with deeper scientific investigation into the Web’sdesign, operati on and impact on society”.Yvonne: It’s true. We've only just begun to understand how useful the World Wide Web can really be, especially for people in developing countries.Rob: So this technological breakthrough, twenty years ago, is something worth celebrating! Now, Yvonne, earlier I asked you a question. On average, howlong does someone spend surfing the net each day in the UK?Yvonne: And I said 27 minutes.Rob: And you were wrong.Yvonne: Oh no!Rob: The average time people spend on the internet each day is a lot longer than that.It's 57 minutes.Yvonne: Oh - and without Sir Tim and his colleagues’ work, it wouldn’t be possible at all.Rob: That’s right. Well, we do hope you’ve enjoyed today’s 6 Minute English.Both: Bye bye.Vocabulary and definitionsanniversary a date that is remembered each year because somethingspecial happenedsurfing searching, looking at, browsing information on the interneta breakthrough an important discovery, development or achievementgratifying satisfying, pleasingheralded signalled something that was going to arrive or happen inthe futurescare stories news that frightens many people unnecessarily, all or partsof which may not be truesocial relationships connections with family and friendsfile cabinets (filing cabinets) furniture that is used to keep documents or papers safe; usually found in offices。
The World-Wide Web
World-Wide WebTim Berners-Lee, Robert CailliauC.E.R.N.CH - 1211 Genève 23timbl@info.cern.ch, cailliau@cernnext.cern.chAbstractThe W3 project merges networked information retrieval and hypertext to make an easybut powerful global information system. It aims to allow information sharing withininternationally dispersed groups of users, and the creation and dissemination ofinformation by support groups. W3’s ability to provide implementation-independentaccess to data and documentation is ideal for a large HEP collaboration. W3 now definesthe state of the art in networked information retrieval, for user support, resource discoveryand collaborative work. W3 originated at CERN and is in use at CERN, FNAL, NIKHEF,SLAC and other laboratories. This paper gives a brief overview and reports the currentstatus of the project.IntroductionThe World-Wide Web (W3) project allows access to the universe of online information using two simple user interface operations. It operates without regard to where information is, how it is stored, or what system is used to manage it. Previous papers give general [1] and technical [2] overviews which will not be repeated here. This paper reviews the basic operation of the system, and reports the status of W3 software and information.OperationThe W3 world view is of documents referring to each other by links. For its likeness to a spider’s construction, this world is called the Web. This simple view is known as the hypertext paradigm. The reader sees on the screen a document with sensitive parts of text representing the links. A link is followed by mere pointing and clicking (or typing reference numbers if a mouse is not available).Fig 1. The basic hypertext model is enhanced by searches.Hypertext alone is not practical when dealing with large sets of structured information such as are contained in data bases: adding a search to the hypertext model gives W3 its full power (fig. 1). Indexes are special documents which, rather than being read, may be searched. To search an index, a reader gives keywords (or other search criteria). The result of a search is another document containing links to the documents found.The architecture of W3 (fig. 2) is one of Array browsers (clients) which know how to presentdata but not what its origin is, and serverswhich know how to extract data but areignorant of how they will be presented.Servers and clients are unaware of the detailsof each other’s operating system quirks andexotic data formats.All the data in the Web is presented with auniform human interface (Fig. 3). Thedocuments are stored (or generatedbyalgorithms) throughout the internet bycomputers with different operating systemsand data formats. Following a link from theSLAC home page (the entry into the Web of aSLAC user) to the NIKHEF telephone book isas easy and quick as following the link to aSLAC Working Note.Fig. 2: Architecture of W3 Providing InformationAuthors can create documents by simply typing files (in plain text, using hypertext SGML markup or a W3 editor) and linking them into the Web. This is most useful in collaborative work: the latest text is accessible on-line, no copies, drafts or out-of-date printouts. If the data is stored in an existing data-base, a server can be tailored to provide its data to the Web. Hypertext links may be made to any data in non-W3 servers (FTP, Gopher, WAIS or internet news) as W3 clients have the ability to present all such data as hypertext.In the case of an existing information system containing a large mass of information, one should consider writing a server to provide a hypertext view of the data without touching the data itself or the procedures by which the database is maintained (Fig. 4). An existing server may be taken as an example to be modified and enhanced to provide the functionality required. Typically, it is modified to call a program which already exists to access the data. The server merely reformats the W3 document address (and/or search criteria) into a request to the program, and then reformats the program output as hypertext.Software statusThe success of the W3 initiative can be attributed to enthusiasts and collaborators in many institutes. The W3 team at CERN has incorporated some of their work into software releases; other work is distributed and maintained by the original authors. This is a summary: details are available on the Web.Client softwareThe initial prototype development for W3 clients was done on two platforms. A “dumb terminal” browser was written at CERN by Nicola Pellow to demonstrate access from lowest common denominator platforms supporting only a C compiler and internet access. This program is now a mature product much in demand both as a simple interactive browser and as a general data access and text formatting tool which can be built into more complex programs.The prototype window-oriented browser and hypertext editor was developed on a NeXTStep™ platform. It has been frozen in its prototype form until further notice.For X-Windows, four clients exist, at various levels of development between alpha and beta test. Differing principally in the underlying toolkits used, each has different and interesting possibilities of extension. Sources of all four are available:The ViolaWWW client was written and is maintained by Pei Wei of O’Reilly Associates.It is a fully-fledged hypertext browser with search facility, bookmarks and history recall panel. At beta test level, this browser has to date been ported to SGI, Sun, IBM rs6000 and DECstation™ platforms.The MidasWWW client has a Motif look-and-feel. It was written recently by Tony Johnson of SLAC using his Midas toolkit.The tkWWW client was written by Joseph Wang at the MIT Athena project, based on the existing “tk” toolkit.The Erwise W3 client was written as a student project by four students at the Helsinki Technical University, and is not maintained.A Macintosh client is being written at CERN with help from FNAL as a stand-alone Macintosh application for any Mac with TCP-IP.For the IBM-compatible PC, a W3 browser is being written on top of Microsoft’s Word for Windows as a CERN supported student project by Alain Favre, with CNAM, France. Neither Mac nor PC browser is available at the time of writing.The clients share a common library of network information access code which is available separately.Server softwareCurrently, W3 servers exist for Unix, VMS and VM and must be configured by system managers. When servers for personal computers are available, we expect a great increase in publishing directly by authors, reviewers and documentation managers. Existing servers include those for:Files File servers run on Unix, VMS or VM to distribute existing filesto hypertext browsers. Directories of the file system arerepresented as hypertext lists of the files they contain. Authorsmay provide plain text files or marked-up hypertext. Anyanonymous FTP server may also be accessed by the W3 clientswith some speed penalty compared to a W3 server.VMS/Help For information in VMS/Help™ format, a server runs under VMS.Oracle A generic Oracle™ server has been written by Arthur Secret(CERN/EISTI) to allow access to Oracle databases from W3clients. This currently accepts SQL “select” statements as searchterms and runs under Unix.GNU Info Written by Philippe Defert (CERN), this “perl” script runs underUnix and provides an existing Gnu Info database of onlinedocumentation as hypertext.Fig 3: Unification for the user Fig. 4: No operative changes for the providerThe Spread of the WebOver the last year, the existence of browsers has prompted several HEP institutes, and several other sites, to put up W3 servers. Thanks to the creativity and vision of those involved, there is a great variety of information available. Whilst the most commonly accessed may be “phone book”-type information from CERN, NIKHEF and SLAC, there is also deeper online documentation. Figure 4 shows locations of some current and prospective server sites (note: Archie, Gopher and WAIS are themselves network information systems, accessible through W3 as a subset of the Web. Only their location of origin is shown).Fig. 4: known servers at September 92Aleph, Opal, and SLD (and, experimentally, D0) have experiment-specific information. At Fermilab, the existing documentation schemes for online and offline systems have been made available among other things. At SLAC, the “WWWizards” have servers running on VM and Unix, making available the “SPIRES” database information (including the popular preprint index), and a database about the “FreeHEP” software collection.Future enhancementsThe next generation of the W3 protocol is being tested at CERN by Carl Barker of Brunel University. The protocol provides simple password based control over access to sensitive information. It also allows client and server programs to negotiate commonly understood data formats. This will open the door to the transfer of graphics files, as well as raw numeric data for manipulation and analysis, and text in an open set of formats such as word processor formats, TeX, and general SGML document types.We have W3 servers and clients running over DECnet™, and aim to release a DECnet-Internet W3 gateway in the near future.Getting startedTo further the spread of W3, we suggest you encourage the adoption of first client programs and then servers at your own site. Information on how to get and install W3 code is available from our line-mode server. On a computer connected to the internet, type:telnet info.cern.chThis will give you the very basic line mode interface. Use it to find out how to install that or more advanced browsers on your local system. The source code, binaries and various articles are available by anonymous FTP from info.cern.ch, under directory /pub/www. (info.cern.ch is currently 128.141.201.74). All information about the W3 project is on the web, so you should look for it there and mail us if you find problems. A plain text version of the installation instructions is included in the tar file for the line mode browser.Also on the Web is information about how to subscribe to the mailing lists we keep for announcements of new facilities and for technical discussions. The W3 team at CERN will also try to answer questions sent to www-bug@info.cern.ch.References[1]T.J. Berners-Lee, R. Cailliau, J-F Groff, B. Pollermann, CERN, "World-Wide Web:The Information Universe", published in Electronic Networking: Research,Applications and Policy, Vol. 2 No 1, Spring 1992, Meckler Publishing, Westport,CT, USA. See this paper for other technical references.[2]T.J. Berners-Lee, R. Cailliau, J-F Groff, B. Pollermann, CERN, "World-Wide Web:An Information Infrastructure for High-Energy Physics", Presented at "ArtificialIntelligence and Software Engineering for High Energy Physics" in La Londe,France, January 1992. Proceedings published by World Scientific, Singapore, ed. D Perret-Gallix.。
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• The terms Internet and World Wide Web are often used in everyday speech without much distinction. However, the Internet and the World Wide Web are not one and the same. The Internet is a global system of interconnected computer networks. In contrast, the Web is one of the services that runs on the Internet. It is a collection of text documents and other resources, linked by hyperlinks and URLs, usually accessed by web browsers from web servers. In short, the Web can be thought of as an application"running" on the Internet.
• When you type an Internet site ,firstly you are bound to type three letters ‘www’.Do you ever doubt of its meaning?Actually, it is the abbreviation of the words ‘world wide web’.Ok ,today ,I will introduce it to you in detail.
• 1. broaden our horizons • 2.make it easy to communicate with the outside world • 3.provide considerable information • 4.make our life more convenient
• 1.result in the decline in students academic performance • 2. Internet addiction bring mental and physical illness • 3. Pornography and violence bring about social security issues
First of all ,let’s start with it’s history. In 1989, Tim Berners-Lee wrote a proposal that referenced ENQUIRE, a and software project he had built in 1980,and described a more elaborate information management system. With help from Robert , he published a more formal proposal (on November 12, 1990) to build a "Hypertext project" called "WorldWideWeb" .By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web. On August 6, 1991, he posted a short summary of the World Wide Web project. This date also marked the debut of the Web as a publicly available service on the Internet. The World Wide Web Consortium was founded by Tim Berners-Lee in October 1994. It was founded at the Massachusetts Institute of Technology Laboratory for Computer Science; a year later, a second site was founded at a French national computer research lab; and in 1996, a third continental site was created in Japan. By the end of 1994, while the total number of websites was still minute compared to present standards, quite a number of notable websites were already active, many of which are the precursors or inspiration for today's most popular services.