• Instructor:Mr. Tawfik Aljobory

• Required: Text editor (e.g. Notepad)• Textbook: HTML, XHTML, and CSS

Bible, Brian Pfaffenberger, Steven M. Schafer,Charles White, Bill Karow,2004

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is a network of computers able to exchange text, graphics, and multimedia information via the Internet.

What Is the World Wide Web?

•The Web is a collection of files organized as a hugehypertext .•Many of these files produce documents called Web pages•Web site - location on a computer somewhere on theInternet that stores a collection of Web pages

http://www.yahoo.com2

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• Web server - computer with special software for transmitting Web pages over the Internet– Domain names prefixed with www

• Home page - identifies the site and contains links to other pages at the site

• Web sites are composed of a series of Webpages– Each page stored as a file– Referred to by a unique URL

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What is the Web?

• URL (Uniform Resource Locator) - an Internet address of a document on a computer– Begins with http://

• HTTP stands for Hypertext Transfer Protocol - the protocol that allows Web browsers to communicate with Web servers

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• Hyper Text Transfer Protocol (HTTP) This is the "native" protocol of the Web, designed specifically to transmit hypertext over networks.

• File Transfer Protocol (FTP) This protocol allows a user to transfer text or binary files among computer hosts across networks.

• Gopher This protocol allows users to share information using a system of menus, documents, or connections to Telnet sessions.

• Network News Transfer Protocol (NNTP) This is the protocol for Usenet news distribution. Usenet is a system for asynchronous text discussion in topic subdivisions called newsgroups.

• Telnet This protocol is used for (possibly remote) logon to a computer host. 7

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• Browsers

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• What is a browser?• Web browsers provide Internet users with

all-purpose client software for accessing many types of servers– Internet Explorer– Netscape– Opera– Chrome– Firefox

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Exactly what does a browser do?A browser fetches and displays Web pages

• The server sends your computer data that’s stored

• The data consists of information that you want to see and HTML tags, codes that tell your browser how to display it

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How Does the Web Work?• The computers that make all these Web

pages available are called Web servers.

On any computer that’s connected to the• Web, you can run an application called a

Web browser. Technically, a Web browser is called a Web client

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• They all speak a common “language,” called HyperText Transfer Protocol (HTTP).

• HTTP It’s a set of rules or• procedures, called protocols, that enables

computers to exchange information overthe Web.) Regardless of where these computers

reside—China, Norway, or Texas—they can communicate with each other through HTTP.

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• Most Web pages contain hyperlinks, which are specially formatted words or

phrases that enable you to access another page on the Web.

• When you click the hyperlink, your computer sends a message called an HTTP request. This message says, in effect, “Please send me the Web page that I want.”

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• If the page isn’t found, you see an• error message, which probably includes

the HTTP code for this error: 404, “Not• Found.”

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• What Is Hypertext?Hypertext is a type of text that contains

hyperlinkswhich enable the reader to jump from one

hypertext page to another.

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• Where Does HTML Fit In?Hyper Text Markup Language (HTML) enables

you to mark up text so that it canfunction as hypertext on the Web.It is

Computer Language understood by internet browser

HTML consists of its own set of symbols that tell Web browsers how to display the page. These symbols, called elements, include the ones needed to create hyperlinks. 21

Standard Generalized Markup Language (SGML), an international standard for marking up text for presentation on a variety of physical devices. The basic idea of SGML is that the

document’s structure should be separated from its presentation:

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