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пособие the Internet.doc
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The History of the Web

The first rumblings toward this concept began immediately after World War II, when scientists were desperately seeking ways to organize and share their accumulated wartime research. In 1945, noted scientist Vannevar Bush published an essay in Atlantic Monthly titled “As We May Think”, which proposed a massive information index that people from all over the world could access and search. Although Bush's system was mechanical (and was never developed), his essay had a profound impact on many who would one day help design the Internet and the World Wide Web. For this reason, Vannevar Bush is often hailed as the theoretical father of the Web.

Given this background, the actual Web was originally conceived as a way for physicists to share their research data. In 1989, Tim Berners-Lee led a team at Switzerland's European Particle Physics Laboratory (CERN) in developing the initial World Wide Web standards. Key among these was the use of hypertext, or “hot” portions of an online document that, when selected, take the user to a related, or "linked," document. For instance, if a user was reading a Web document about dinosaurs and selected the hypertext word “Tyrannosaurus”, he or she would go directly to a document dealing specifically with that species of dinosaur.

Computerized hypertext was pioneered by researcher Ted Nelson in a system called Xanadu, which he created in the early 1960s. Although Xanadu was never fully realized, many of the Web's developers – including Berners-Lee – have cited it as an influence on their work.

The next great innovation for the Web came in 1992, when programmers from the National Center for Supercomputing Applications (NCSA) at the University of Illinois developed the Mosaic browser, a software application that displayed not only the text of a Web document (or page), but embedded graphic elements as well. By bringing multimedia to the Web, Mosaic vested it with enormous potential.

Today, several Web browsers are available for IBM, Macintosh and UNIX-based computers, and most of the major online services include Web browsers in their standard software packages. And the Web is growing at a phenomenal rate. According to Interactive Week magazine, the number of Web servers (computers that store Web pages) surged from fewer than 3,500 in April 1994 to more than 40,000 in July 1995. And in February 1997, the computing firm Network Wizards determined the number of commercial domains alone to be well over 700,000.

A Quick Tour of a Typical Web Site

A Web site may consist of a single Web page, or may comprise multiple, interconnected pages. The following is a view of how the CenterSpan home page appears through a popular browser:

  1. Browser tools help you navigate around the Web. These vary among browsers, but most include tools for moving back and forth between pages, saving data to your hard disk, and controlling how Web pages will appear on your screen.

  2. A “Bookmark” list, “favorites” list or “hotlist” lets you save the names and locations of favorite sites for easy reference (usually accessible through pull-down menus).

  3. The Uniform Resource Locator (URL) is the address of a Web site. URLs for Web pages begin with the code http:// ("http" stands for hypertext transfer protocol).

  4. Some Web pages contain special graphic buttons that, when clicked, take you to another resource as would a regular hotlink.

  5. Hypertext hotlinks are connections to other pages and resources. To access, just click on them with your mouse or trackball. Most pages contain hotlinks throughout the text, as well as lists of links to other sites judged by the author/sponsor to be of particular interest. Some sites contain hotlinks to places where you can download software, listen to a sound file, or view a video clip.

  6. CenterSpan uses several applets, or small program segments run by Java, ActiveX or some other protocol. Applets are downloaded when you access a Web site, and run only as long as you remain at that location. Applets can perform a variety of functions; the applet on the CenterSpan home page generates a scrolling banner, like the example below. If your browser does not have the capability to display Java applets, you will not be able to see this banner.

  7. To make it easy to contact the author or sponsor of a Web site, most contain one or more E-mail links. Clicking on such a link brings up a form where you can type an E-mail message to a pre-set address (not shown here).

CenterSpan is among more elaborate Web sites that contain forms, where you can submit information in an easy-to-follow format, and bulletin board features that allow you to post information for others to see.

Task 10. Make up 10 questions concerning the contents of the text and then retell the text.