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Linking and Publishing Basic
Web Pages
Chapter 3
XHTML Introductory
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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
XHTML Introductory
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Linking Web Pages
• 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)
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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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Uniform Resource Locators
• 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”
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Uniform Resource Locators
• 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
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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 contenttype, 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 contenttype <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
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