xhtml introductory1 linking and publishing basic web pages chapter 3

XHTML Introductory 1

Linking and Publishing Basic Web Pages

Chapter 3

XHTML Introductory 2

Objectives

In this chapter, you will:

• Link Web pages

• Study Uniform Resource Locators (URLs)

• Create absolute and relative links

• Create links within the same Web page

• Learn how to publish your Web pages

• Study metadata

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• You activate a hypertext link by clicking it with your mouse button

• A hypertext link in an HTML document is underlined and often displayed in a vivid color

• The text or image used to represent a link on a Web page is called an anchor

• You create a basic hypertext link using the <a> element (the a stands for anchor)

Linking Web Pages

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Linking Web Pages

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Linking Web Pages

• It is not always necessary to use images for links because basic text links, if properly placed on a Web page, can be just as effective

• It takes much less time to create a text-based hyperlink than it does to design an image to use as a hyperlink

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• Hypertext Transfer Protocol (HTTP)

– manages the hypertext links that are used to navigate the Web

– ensures that Web browsers correctly process and display the various types of information contained in Web pages (text, graphics, audio, and so on)

• The protocol portion of a URL is followed by a colon, two forward slashes, and a host

• A host refers to a computer system that is being accessed by a remote computer

• The host portion of a URL is usually www for “World Wide Web”

Uniform Resource Locators

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• Domain name

– a unique address used for identifying a computer, often a Web server, on the Internet

– consists of two parts separated by a period

– The first part of a domain name is usually text that easily identifies a person or an organization, such as DonGosselin or Course

– The last part of a domain name, known as the domain identifier, identifies the type of institution or organization

– Common domain identifiers include .biz, .com, .edu, .info, .net, .org, .gov, .mil, or .int

Uniform Resource Locators

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Uniform Resource Locators

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Absolute and Relative Links

• An absolute URL refers to the full Web

address of a Web page or to a specific drive

and directory

• A relative URL specifies the location of a file

relative to the location of the currently loaded

Web page

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Linking Within the Same Web Page

• Bookmarks are internal links within the current document and can be a particularly effective tool for helping users navigate through a long Web page

• You create bookmark links by using the id attribute

• The standard id attribute uniquely identifies an individual element in a document

• Any element that includes an id attribute can be the target of a link

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Linking Within the Same Web Page

• The id attribute replaces the name attribute that is used in HTML

• Many older browsers do not recognize the id attribute

• To address this problem the name attribute was not deprecated in the <a> element

• To ensure that your links are valid in older browsers, you must use both the id and name attributes inside an <a> element and assign the same value to both attributes

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Publishing Your Web Pages

• Web hosting refers to the publication of a Web site for public access

• You can use your own computer to host your Web site, provided it is connected to the Internet

• Although you may have a state-of-the art desktop computer, it will probably still be slower than a professional-strength Web server, which is a special type of computer used for hosting Web sites

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Publishing Your Web Pages

• Most people use an Internet Service Provider (ISP) to host their Web sites

• An ISP provides access to the Internet along with other types of services including e-mail

• Most ISPs have extremely fast Internet connections using advanced fiber-optic connections that are light years more powerful than a dial-up modem

• ISPs also have very large and powerful Web servers, along with the expertise and manpower to maintain and manage them

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Domain Name Registration

• One important decision you need to make is what to use for a domain name

• To find out the availability of a domain name and register it, you must contact a domain name registrar

• Domain names are stored in a master database that is maintained by InterNIC, the organization responsible for the registration of domain names and IP addresses

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Domain Name Registration

• A popular domain name registrar is Network Solutions, a division of VeriSign

• Once you register your domain name, you need to notify your ISP of your domain information

• Usually, it is easier to register your domain name through the ISP you intend to use because they can automatically handle the details of setting up the domain for you

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File Transfer Protocol

• File Transfer Protocol (FTP) is the protocol used for transferring files across the Internet

• A Web browser is not the target for files transferred by FTP

• FTP simply transfers files between an FTP client (your computer) and an FTP server (a server capable of running FTP)

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File Transfer Protocol

• To publish your Web site, you must upload your files to your ISP’s FTP server

• Your ISP will give you a user name and password that you must use to log into the FTP site

• Various types of commercial shareware software exist that you can use to access an FTP site

• Many HTML Editors such as FrontPage have built-in commands that you can use to log into an FTP server and upload your files

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File Transfer Protocol

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Advertising Your Web Site

• Web directories are listings of Web sites that have been compiled by humans

• Search engines use software to “crawl” or “spider” their way through the Web and automatically compile an index of Web sites

• Yahoo! is an example of a Web directory that is compiled by humans, whereas HotBot is an example of a search engine that finds Web sites automatically

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Advertising Your Web Site

• Waiting for search engines and directories to come to you is not the best way of advertising your site

• Your best bet is to submit your site to a search engine or Web directory when you first publish it or whenever you make major changes to it

• Most search engines and directories have a button that allows you to submit a site

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Advertising Your Web Site

• Directories such as Yahoo! that are compiled by humans require that you include a description of your Web site when you submit it

• In comparison, to find information about a Web site, a search engine’s “spider” (also called a “crawler” or “robot”) will visit a page on the site, record information about the page in an index, and then follow any links to other pages within the site and index their information

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Metadata

• The term metadata means information about information

• In a Web page, you use the <meta> element to provide information to search engines and Web servers about the information in your Web page

• You must place the <meta> element within the <head> element

• You can use three primary attributes with the <meta> element: name, content, and http-equiv

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The name Attribute

• You use the name attribute to define the name of the information you want to provide about the Web page

• You can use any text you like as the value of the name attribute

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The name Attribute

• Two values that are used by some search engines are description and keyword

– Many search engines create a description of a Web page based on the first 200 characters following the opening <body> tag, unless the Web page includes a description <meta> element

– Keywords are the words that describe the type of Web page a user is looking for and will likely type into a Web directory or search engine

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Hiding Web Pages from Search Engines

• Your Web site may includes pages that you do not want to be included in any search engine indexes

• For instance, you may have a page that stores personal information or private data that, although not private enough to encrypt using special security software or a protocol such as HTTPS, should not be returned to a user who performs a search in a search engine

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Hiding Web Pages from Search Engines

• You can inform search engine spiders that you do not want certain pages on your site to be indexed by placing a file named robots.tx in the root directory of the Web server that hosts your Web site

• This technique is called the Robots Exclusion Protocol

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The http-equiv Attribute

• When a user wants to access a Web page, either by entering its URL in a browser’s Address box or by clicking a link, the user’s Web browser asks the Web server for the Web page in what is referred to as a request

• What the Web server returns to the user is called the response

• One part of the response is the requested Web page

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The http-equiv Attribute• The response header is sent to the Web browser before

the Web page is sent in order to provide information that the browser needs to render the page

• One of the most important pieces of information in the response header is the type of data, or content-type, that the server is sending

• One important use of the <meta> element is to specify a document’s character encoding

• The W3C strongly encourages the use of content-type <meta> elements to specify an XHTML document’s character set

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Summary

• The text or image used to represent a link on a Web page is called an anchor

• Hypertext Transfer Protocol (HTTP) manages the hypertext links that are used to navigate the Web

• A host refers to a computer system that is being accessed by a remote computer

• An absolute Uniform Resource Locator (URL) refers to the full Web address of a Web page or to a specific drive and directory

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Summary

• A relative URL specifies the location of a file relative to the location of the currently loaded Web page

• Web hosting refers to the publication of a Web site for public access

• Domain names are stored in a master database that is maintained by InterNIC, the organization responsible for the registration of domain names and Internet Protocol (IP) addresses

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Summary

• File Transfer Protocol (FTP) is the protocol used for transferring files across the Internet

• Search engines use software to “crawl” or “spider” their way through the Web and automatically compile an index of Web sites

• You use the <meta> element to provide information to search engines and Web servers about the information in your Web page