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What is the Web? The World Wide Web (or WWW or Web for short) and the Internet are terms that are often used as though they mean the same thing. Actually, the Web is only a portion of the Internet. So let's start with finding out what the Internet is. The Internet The Internet is simply a network of computer networks. But there is nothing simple about this network. Unlike most networks, the Internet is not under a central control. From the beginning, this network, which was started by the US Department of Defense, has been designed to be very hard to shut down. The idea was to have a network that could have big chunks blown up without losing the whole network. It has many, many connections between the member networks and no one place controls the whole network. In fact, there is no one "in charge" of anything about the Internet except the assigning of addresses! It is amazing that thousands of people working all over the world can manage to create such a huge system that actually works. The original purpose of the Internet was to enable people in different locations to share text-only documents. Now there is much more you can do using the Internet. You can send and receive email messages; you can search the world for particular files or for files that contain particular words; you can have a live conversation using typed text or voice or even video; you can read electronic magazines and newspapers; you can check on the weather forecast or the score of a ball game; you can play computer games with several people at once; you can post messages to newsgroups on a common topic; you can buy books, CDs, software, wine, or just about anything. The Web The Web is that part of the Internet that uses hypertext documents, also called Web documents or Web pages. Words in hypertext are generally underlined and in a special color, like this. They have an address attached to them so that clicking on the hypertext accesses the file at that address. The file can be one that is on the viewer's own computer (like C:\My Documents\letters\5-10-98 to mother.doc) or halfway around the world (like http://www.microsoft.com/default.asp). Such text is called a hypertext link, hyperlink, or just a link. Web pages have come a long way from the original plain text documents. Now they can show movies, play songs, and react to what the user clicks on in many imaginative ways. It was only in 1989 that development began by CERN (the European Laboratory for Particle Physics) on the beginnings of what became the World Wide Web. The physicists wanted the ability to handle all Internet work though a single interface, to simplify the sharing of documents between their widely scattered sites. By 1992 the system was functioning well enough to publicize and invite others to move to the new approach. Very quickly numerous browsers were developed for a variety of operating systems. The Web soon became the most popular way to access the resources on the Internet. DN September 2003 This information was taken from Jan’s Illustrated computer literacy 101 found at http://www.jegsworks.com/Lessons/web/basics/ HTML Hypertext documents are written in HTML (HyperText Markup Language), a coding language that does much more than just create hyperlinks. HTML code puts special marks in a text document to tell browser software how to display the text. For example <FONT FACE=ARIAL COLOR=#FF0000> means to use the font Arial and the color red when displaying the text. The language's instructions are based on English. Each new version of the HTML standards adds more formatting choices and the ability to do other things like playing sounds and running animations. Address of a Web page Each web page has a unique address called a URL, or Universal Resource Locator, which tells where a file is located among all the computers that are part of the Internet. A URL usually has three parts: protocol://domain/path Example, http://www.microsoft.com/windows/downloads/default.asp Protocol: tells the computer what kind of coding to expect. For web pages the address always starts with http:// which stands for hypertext transfer protocol. For a site that just downloads files you might use ftp:// which stands for file transfer protocol. There are other protocols that you are less likely to use. Domain: the unique name for the computer to which you are connecting. All domain names have a 4-part number address like 207.46.130.150 but most have a name using letters, too, like www.microsoft.com (which is much easier to remember!). A dot character always separates the parts of a name. The www stands for World Wide Web and is used for most web pages as the first part of the domain name. The com part stands for "commercial" and is one of several extensions allowed for the top level domain. Others include gov for government, edu for educational institution, org for organization, mil for military, and net for network. It is common in many countries to include the country identifier in the domain, such as .us for the United States, .fr for France, or .ar for Argentina. List of country codes Seven new top-level domain names have been approved by ICANN (Internet Corporation for Assigned Names and Numbers): .pro, .biz, .coop, .info, .museum, .aero, and .name. Path: is the list of folders on the computer, down to the actual file, like /windows/downloads/default.asp If no file name is listed at the end of the path, the browser will look for the default file, usually named index.html . If no such file is found, the browser will try to show a list of the files in the last folder in the path. It may find that it needs special permission or a password to show the list of files. You can expect to see htm or html as the extension for most web pages. The extension asp (Active Server Page) is used for a page that uses special codes from Microsoft in addition to DN September 2003 This information was taken from Jan’s Illustrated computer literacy 101 found at http://www.jegsworks.com/Lessons/web/basics/ HTML. The extension shtml ( Secure HTML) is for pages that are encrypted because they involve sensitive information like credit card numbers. The spelling and punctuation of an Internet address must be exactly right, including the use of upper case letters. Many servers that handle web pages use the operating system UNIX, for which myfile.htm, MyFile.htm, myfile.HTM are all different names. Type carefully! A forward slash / is not the same as a back slash \. A colon : and a semicolon ; are not the same. A comma , is not the same as . the dot character. Web addresses are followed by an extension that identifies its domain. .com Commercial DN .gov Government .edu educational .org Organization .mil military .net network September 2003 This information was taken from Jan’s Illustrated computer literacy 101 found at http://www.jegsworks.com/Lessons/web/basics/