CUT4e_Ch07_Presentationx

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Chapter 7 The Internet and the
World Wide Web
Chapter 7
The Internet and the
World Wide Web
© Paradigm Publishing, Inc.
7-1
Presentation Overview
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The Internet: A Global Network
Connecting to the Internet
Navigating the Internet
Viewing Web Pages
Searching for Information on the Internet
Using Newer Internet Applications
Respecting the Internet Community
© Paradigm Publishing, Inc.
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The Internet: A Global
Network
How does the Internet create a global
community?
The Internet is the largest computer network in
the world. It can be used for
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Communications
Entertainment
Electronic commerce
Research
Distance learning
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The Internet: A Global
Network
Communications
– Today, electronic mail
(e-mail) is the most
widely used Internet
application.
– It allows users to
create, send,
receive, save, and
forward messages
in electronic form.
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The Internet: A Global
Network
Communications
– A chat room is an application that allows users
to chat in real-time dialogue.
– People can also have one-on-one real-time
conversations through instant messaging.
– A blog is a frequently updated journal
containing chronological entries of personal
thoughts and links posted on a Web page.
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The Internet: A Global
Network
Communications
– In recent years, social networking services
have become very popular, allowing users to
create their own personal Web spaces and
interact socially.
– A message board, or forum, is an
electronically stored list of messages that
anyone with access to the board can read.
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The Internet: A Global
Network
Communications
– Many people now work from home, using a
computer, modem, and telephone line. This is
known as telecommuting.
– Sites such as YouTube offer free video
streaming.
– Users can also communicate by transferring
files to and from computer systems using File
Transfer Protocol (FTP).
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The Internet: A Global
Network
Comparison of E-mail, Cell Phone, and IM Usage in
the United States
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The Internet: A Global
Network
Entertainment
– There are an enormous amount of online
games available—some are free and some
require a purchase.
– Virtual casinos offer online gambling, a novel
and controversial entertainment feature.
– Online services allow users to download music
and video.
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The Internet: A Global
Network
Electronic Commerce
– The Internet exchange of business information,
products, services, and payments is known as
electronic commerce.
– It is commonly divided into two categories:
• Business-to-consumer (B2C)
• Business-to-business (B2B)
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The Internet: A Global
Network
Retail Sales: Total and Online in 2008
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The Internet: A Global
Network
Research
– The Internet gives users interested in any topic
access to books, periodicals, photos, video, and
sound files from around the world.
– These materials can be read online or
downloaded for future use.
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The Internet: A Global
Network
• Distance Learning
– The back and forth electronic transfer of
information and course materials between
learning institutions and students is known as
distance learning.
– A course presented in this manner is called an
online course.
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Connecting to the Internet
What resources are needed to connect to the
Internet?
– Computer, PDA, or smartphone
– Network card, digital subscriber line (DSL), or
modem
– Network, telephone line, or cable connection
– Web browser
– Account with an Internet service provider (ISP)
or value added network (VAN)
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Connecting to the Internet
Types of Internet Connections
– Dial-up access allows access to the Internet
over a standard telephone line.
– Local area network Internet connections
connect users to the Internet on a direct wire.
– Broadband Internet access is provided by
cable companies.
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Connecting to the Internet
Types of Internet Connections
– Wireless is the fastest growing segment of
Internet service; it provides access through
radio waves.
– Satellite requires a satellite dish and a modem
to connect to the Internet.
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Connecting to the Internet
Comparison of Internet Connection Speeds
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Navigating the Internet
What capabilities do Web browsers offer?
– Automatic identification and connection to any
local port providing a connection to the Internet
– HTML code viewing
– Java applet support
– Easy-to-use interfaces that allow for control
commands such as a favorites list, a stop access
button, and a go-back button
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Navigating the Internet
An Internet Protocol (IP) address is a fourgroup series of numbers separated by periods
representing a server on the Internet.
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Navigating the Internet
• A Uniform (or Universal) Resource Locator
is a pathname describing where information
can be found on Internet.
• The parts of a URL are
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The communications protocol (HTTP)
Format information (www)
Domain name (Amazon)
Domain suffix (.com)
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Navigating the Internet
Common Domain Suffixes Used in URLs
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Navigating the Internet
Country Name Abbreviations in URLs
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Navigating the Internet
The Path of a URL
A URL directs routers
and servers to display the
specific Web page
identified by the URL.
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Navigating the Internet
Packet Switching
Messages sent over the
Internet are broken into
separate files, or packets,
and then are reassembled
at the destination.
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Viewing Web Pages
• A Web page is the term for a single
document viewable on the World Wide
Web.
• A Web site comprises all of the Web pages
composing the site.
• The home page is an overview of the
information contained within the site.
• A portal is a site that acts as a gateway to
access a variety of information.
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Viewing Web Pages
Web pages are created using a programming
language called Hypertext Markup Language
(HTML).
– A markup language is a set of specifications
describing the characteristics of elements that
appear on a page.
– A hypertext document presents information
enhanced with links to other documents.
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Viewing Web Pages
• HTML tags are located within angle brackets.
• The text in between the tags is content that visitor
using a Web browser will view.
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Viewing Web Pages
An new and improved Web language called
Extensible Markup Language (XML) is
becoming increasingly popular.
– XML organizes and standardizes the structure
of data so that computers can communicate
with each other directly.
– XML is more flexible than HTML, as it is a
metalanguage—a language for describing
other languages.
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Viewing Web Pages
Audio, Video, and Animation Elements
– Java applets provide the ability to program
online games and highly interactive interfaces.
– Cookies store preference information, such as
user IDs and passwords.
– Plug-ins extend the capabilities of Web
browsers by improving graphic, sound, and
video elements.
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Viewing Web Pages
Internet Advertising
– A banner invites viewers to click it to go to a
new Web site selling a product or service.
– A pop-up window advertisement “pops”
unexpectedly into the middle of the screen.
– A blind link is a link that misrepresents its true
function to get people to click on it.
– A hi-jacker causes efforts to reach a certain
page to be redirected to another page.
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Viewing Web Pages
Each site on a WebRing
maintains a link to the
next site, forming a ring.
WebRings are generally
moderated by someone
who wants to help people
find Web sites that would
not otherwise be easily
accessible.
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Searching for Information on
the Internet
Users can search for and
retrieve information
from Web pages by using
a search engine.
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Searching for Information on
the Internet
Differences between search engines are
related to
– The number of Web pages the engine catalogs
– The search methodology used
– The number of different search tools available
to refine searches
– Whether or not the engine accepts fees from
Web sites to place their names at the top of
search results lists
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Searching for Information on
the Internet
Search Techniques
– It is important to place the right keywords (also
called search terms) in a search engine’s search
text box.
– Advanced searching employs logic statements
known as search operators to refine searches.
The most common search operators are AND, OR,
and NOT.
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Using Newer Internet
Applications
Peer-to-peer (P2P) file sharing allows people to
download material directly from other users’ hard
drives.
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Using Newer Internet
Applications
Internet Telephony
– This technology, also called Voice over IP
(VoIP), allows two or more people to use the
Internet to make telephone-style calls.
– Voices are digitized and broken down into
packets so that they can be sent anywhere.
– VoIP can be used computer-to-computer, via
Internet-ready phones, and via analog telephone
adapters.
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Using Newer Internet
Applications
Streaming Audio and Video
– An alternative to downloading music or video
is to access it using streaming, which sends a
continuous stream of data to the receiving
computer, where it is immediately played.
– Streaming helps to protect copyrighted material
because a complete copy is not downloaded, so
it cannot be copied and shared.
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Using Newer Internet
Applications
• Webcams are tiny
cameras that allow
conversations over the
Web through live
video transmission.
• Audio mail is a type of
electronic mail that
allows people to
transmit messages by
voice.
© Paradigm Publishing, Inc.
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Respecting the Internet
Community
What are some safeguards for good Internet
behavior?
– Netiquette is a collection of rules and
guidelines that define good Net behavior.
– Moderated environments have a moderator
who can filter messages and ban people who
break the rules.
– Net neutrality states that all net traffic shall be
treated with equal priority.
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Respecting the Internet
Community
What are some safeguards for good Internet
behavior?
– The Digital Millennium Copyright Act of
1998 generally prohibits people from defeating
software encryption programs and other
copyright safeguards.
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Respecting the Internet
Community
Core Rules of Netiquette
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Respecting the Internet
Community
What are some points to remember when
sending e-mail messages?
– Once sent, they cannot be retrieved.
– A permanent copy of the e-mail probably
remains somewhere on the Internet.
– E-mail is easily forwarded or copied.
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On the Horizon
Based on the information in this chapter and
your own experience, what do you think is on
the horizon?
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