Transcript Chapter_02

Teachers Discovering Computers
Integrating Technology and
Digital Media in the Classroom
4th Edition
Chapter 2
Communications, Networks, the
Internet, and the World Wide Web
Chapter Objectives
 Define communications
 Identify the basic components of a
communications system
 Describe how and why network computers are
used in schools and school districts
 Explain how the Internet works
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Chapter Objectives
 Describe the World Wide Web portion of the
Internet
 Explain how Web documents are linked to one
another
 Explain the use of Web browser software
 Explain how to use a Web search tool to find
information
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Chapter Objectives
 Explain how Internet services such as e-mail,
newsgroups, chat rooms, and instant messaging
work
 Describe the educational implications of the
Internet and the World Wide Web
 Describe different ways to connect to the Internet
and the World Wide Web
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What Is Communications?
 A process in which two or more computers or
devices transfer data, instructions, and
information
 Sometimes called telecommunications
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What Is Communications?
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Electronic mail (e-mail)
Voice mail
Fax (facsimile)
Telecommuting
Online services
Videoconferencing
Internet
World Wide Web
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Communications Networks
 Basic communications system
 Two computers, one to send and one to receive
data
 Communications devices that send and receive
data
 A communications channel over which data is sent
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Communications Networks
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Communications Networks
 Communications
channel
 Transmissions media
 Twisted-pair cable
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Communications Networks
 Digital vs. analog
signals
 Modem
 External modem
 Internal modem
 Network interface
cards
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Communications Networks
 Local Area Networks (LAN)
 Covers limited geographical area
 Server manages resources
 Wide Area Networks (WAN)
 Covers large geographical area
 Can consist of several LANs
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Communications Networks
 Home Networks
 Connects multiple
computers in your
home
 Share Internet
access
 Share peripherals
 Can be wired or
wireless
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Networking the Classroom, School,
and District
 School network server
 Example classroom
 Three Macintosh
computers
 Printer
 Example school network
 Classrooms
 Administration
 Computer lab
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Networking the Classroom, School,
and District
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Networking the Classroom, School,
and District
 Example school district
 Central office
 Various schools
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Networking the Classroom, School,
and District
 Wireless schools and
classrooms
 Keep in touch with
family and friends
from anywhere
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Smart pagers
Smart phones
Handheld computers
Notebook computers
 Wireless technology
brings the computer
lab to students
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Networking the Classroom, School,
and District
 High-Speed or Broadband Access
 Government works to provide high speed Internet
access to classrooms
 Broadband technology transmits signals at much
faster speeds
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The Benefits of Computer Networks
in Education
 Sharing of computer
hardware, software,
and data resources
 Unlimited educational
resources
 Communicate with
other educators and
students
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What Is the Internet?
 Worldwide group of connected networks that
allow public access to information and services
 No single organization owns or controls
 Estimated over one billion users
 Variety of users
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What Is the Internet?
The world’s largest network is the Internet, which is a
worldwide collection of networks that link together millions
of businesses, governments, educational institutions, and
individuals.
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History of the Internet
 Started as a network of four computers at the
University of California at Los Angeles in 1969
 Advanced Research Projects Agency (ARPA) ARPANET
 More than 200 million computers today
 Backbone first provided by National Science
Foundation (NSF) - NSFnet
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History of the Internet
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History of the Internet
 Backbone now provided by variety of
corporations
 Various organizations help define standards
 Internet2 (I2)
 Extremely high-speed network
 Develop and test latest Internet technologies
 Members include over 190 universities in the United
States, along with 60 companies and the United States
government
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How the Internet Works
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Data is divided into packets
Routers send packets across the Internet
Packet switching
Transmission control protocol/Internet protocol
(TCP/IP) is the communications protocol used by
the Internet
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How the Internet Works
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How the Internet Works
 Internet Service Providers, Online Service
Providers, and Wireless Internet Service
Providers
 Have permanent connections to the Internet
 Provide temporary connections to individuals and
companies for a fee
 Regional and national ISPs
 Online service providers offer members only areas
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How the Internet Works
 Connecting to the Internet
 Business or school network connected to the
Internet
 Dial-up access
 ISDN
 Cable TV (CATV)
 Digital subscriber line (DSL)
 Power line communications (PLC)
 Public Internet access point
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How the Internet Works
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How the Internet Works
 The Internet Backbone
 Acts as a highway
 National ISPs use dedicated lines to connect
directly to the Internet
 Regional ISPs connect through leased lines to
national ISPs
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How the Internet Works
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How the Internet Works
 Internet Addresses
 Numeric addresses
 Domain name
 Domain type abbreviations
 Country code abbreviations
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How the Internet Works
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The World Wide Web
 Started in the early
1990s
 Hyperlinks
 Uniform Resource
Locator (URL)
 Hypertext transfer
protocol
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The World Wide Web
 How a Web Page
Works
 Hypertext
 Hyperlinks
 Target
 Relative
 Absolute
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The World Wide Web
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Discovery learning
Web surfing
Webmaster
Hypertext markup language (HTML)
Web publishing
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The World Wide Web
 Web Browser
Software
 Interprets HTML and
displays Web pages
and enables you to
link to other Web
pages and Web sites
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The World Wide Web
 Web Browser
Software
 Mosaic
 Netscape Navigator
 Microsoft Internet
Explorer
 Microbrowsers
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The World Wide Web
 Searching for
Information on the
Web
 Directory maintained
by a search engine
company
 Helps find
information on the
Web
 Search engine
 Subject directory
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The World Wide Web
 Multimedia on the Web
 Web pages incorporate graphics, animation,
audio, video, and virtual reality
 Plug-ins
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The World Wide Web
 Multimedia on the
Web
 Graphics
 Used to enhance textbased Internet
 Graphics formats
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The World Wide Web
 Multimedia on the
Web
 Graphics
 Used to enhance textbased Internet
 Graphics formats
 Thumbnails
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The World Wide Web
 Multimedia on the Web
 Animation
 Marquees
 Animated GIFs
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The World Wide Web
 Multimedia on the
Web
 Audio
 MP3, WAV, and WMV
formats
 Players
 Streaming audio
 RealAudio
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The World Wide Web
 Multimedia on the
Web
 Video
 Streaming video
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The World Wide Web
 Multimedia on the Web
 Virtual Reality
 Simulation of real or
imagined environment
that appears as a threedimensional (3-D) space
 VR worlds
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Other Internet Services
 E-mail
 Primary communication method for both personal
and business use
 E-mail programs
 Mailbox
 Mail server
 E-mail address
 User name
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Other Internet Services
 FTP (file transfer
protocol)
 FTP sites and
servers
 Allows file downloads
and uploads
 Anonymous FTP
 FTP programs
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Other Internet Services
 Newsgroups
 Online area in which users conduct written
discussions about a particular subject
 Usenet
 News server
 Newsreader
 Article
 Posting
 Threaded discussion
 Message board
 Blog
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Other Internet Services
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Other Internet Services
 Mailing Lists
 Group of e-mail names and addresses given a
single name
 Subscribing and unsubscribing
 LISTSERVs
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Other Internet Services
 Chat Rooms
 Real-time conversation
 Chat rooms
 Chat clients
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Other Internet Services
 Instant Messaging
 See when one or
more people are
online
 Exchange messages
and files
 Join a private chat
room
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Other Internet Services
 Role-Playing Games (RPGs)
 Massively Multiplayer Online Role-Playing
Games (MMORGs)
 Facebooks
 Podcasting
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Other Internet Services
 Internet telephony
 Voice over IP
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Netiquette
 Internet etiquette
 The code of acceptable
behaviors users should
follow while on the
Internet
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Internet Security
 Firewall
 Filtering software
 Acceptable Use Policy (AUP)
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The Impact of the Internet and the
World Wide Web on Education
 The Web is the Gutenberg
printing press of modern
times
 Collaboration with other
teachers and students
 ePALS
 New instructional
strategies
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The Future of the Internet
and the World Wide Web
 In the next few years, the Internet will connect most of the
world’s computers
 By 2007, more than one billion wireless communication
devices will be in use worldwide, and many of these
products will have the ability to access the Web wirelessly
 All K-12 teachers will have access to high-speed Internet
in their classrooms
 Wireless networks, wireless notebook computers,
wireless mobile labs, wireless Tablet PCs, and other
wireless devices will become commonplace in K-12
education
 Everyday home and office appliances and other devices
that use embedded computers, such as automobiles, will
have built-in Internet access capabilities.
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The Future of the Internet
and the World Wide Web
 Web search capabilities will be more intelligent and
focused
 Within a few years, the Web will operate at speeds 10,000
times faster than today
 Businesses will continue to be the driving force behind the
Web’s expansion
 Increased access speeds and greater availability will
allow teachers and students to view thousands of fullmotion videos over the Web
 The Web will become an integral part of all education and
will revolutionize the way students learn core subjects
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Chapter Summary
 Define communications
 Identify the basic components of a
communications system
 Describe how and why network computers are
used in schools and school districts
 Explain how the Internet works
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Chapter Summary
 Describe the World Wide Web portion of the
Internet
 Explain how Web documents are linked to one
another
 Explain the use of Web browser software
 Explain how to use a Web search tool to find
information
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Chapter Summary
 Explain how Internet services such as e-mail,
newsgroups, chat rooms, and instant messaging
work
 Describe the educational implications of the
Internet and the World Wide Web
 Describe different ways to connect to the Internet
and the World Wide Web
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Teachers Discovering Computers
Integrating Technology and
Digital Media in the Classroom
4th Edition
Chapter 2 Complete
Communications, Networks, the
Internet, and the World Wide Web
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An extensive, current list of Web sites in various categories
can be found at: http://www.scsite.com/tdc4
Click any chapter at the top of the Web page and then click
Guide to WWW Sites on the left sidebar.
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Search Techniques
 Using a subject directory
 Using a search engine
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Using a Subject Directory
 Provides categorized lists of links
 Arranged by subjects
 This example will show you how to find
information on K-12 mathematics
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Using a Subject Directory
 Start your browser and
then enter the URL
www.yahoo.com in the
Address text box. When
the Yahoo! home page is
displayed, scroll down and
then point to the
Education link
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Using a Subject Directory
 Click Education. When the
Education page is
displayed, point to the K12 link, as shown in
Figure 2. Each time you
click a category link, you
move closer to the topic
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Using a Subject Directory
 Click K-12. When the K12 page is displayed,
point to Mathematics
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Using a Subject Directory
 Click Mathematics. The
browser window displays
a listing of sites dealing
with K-12 mathematics.
Scroll down and then
point to Ask Dr. Math.
Notice that the description
after the link says that this
is a question-and-answer
service for K-12 math
students and their
teachers
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Using a Subject Directory
 Click Ask Dr. Math. When
the page appears, explore
the site to see if this type
of Web site can help you
with your assignment
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Using a Search Engine
 Search many Web sites for information you are
seeking
 Carefully craft your keywords to limit the search
 This example uses the Google search engine to
search for the phrase, “ask math questions”
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Using a Search Engine
 Start your browser and
then enter the URL
www.google.com in the
Address text box. When
the Google home page is
displayed, type ask math
questions in the Search
text box and then point to
the Google Search button
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Using a Search Engine
 Click the Google Search
button. When the results
of the search are
displayed, scroll through
the links and read the
descriptions. Point to The
Math Forum - Ask Dr.
Math link
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Using a Search Engine
 Click the Math Forum Ask Dr. Math link to
display the Ask Dr. Math
home page
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Google Scholar
 Allows users to search for
scholarly literature
 Find articles from a wide
variety of academic
publishers, professional
societies, preprint
repositories, and
universities
 www.scholar.google.com
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Limiting the Search
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Guides to Successful Searching
 Use nouns as keywords, and put the most important
terms first
 Use the asterisk (*) to find plurals of words. For
example: retriev* returns retrieves, retrieval, retriever,
and any other variation
 Type keywords in lowercase to find both lowercase
and uppercase variations
 Use quotation marks to create phrases so the search
engine finds the exact sequence of words
 Use a hyphen alternative. For example, use email
OR e-mail
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Guides to Successful Searching
 Limit the search by language
 Use uppercase characters for Boolean operators in
your search statements to differentiate between the
words and operators
 Before you use a search engine, read its Help
 The Internet contains many search engines. If your
search is unsuccessful with one search engine, try
another
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Popular Search Sites
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Search Tools for Education
 Ask Jeeves for Kids
 ajkids.com
 Awesome Library
 awesomelibrary.org
 Ben’s Guide to U.S. Government for Kids
 bensguide.gpo.gov
 Blue Web’N
 www.kn.pacbell.com/wired/bluewebn
 Busy Teachers’ WebSite K-12
 www.ceismc.gatech.edu/busyt
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Search Tools for Education
 Education World
 www.education-world.com
 EduHound
 www.eduhound.com
 emTech
 www.emtech.net
 FirstGov for Kids
 kids.gov
 Great Web Sites for Kids
 www.ala.org/alsc/children_links.html
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Search Tools for Education
 Kathy Schrock’s Guide for Educators
 school.discovery.com/schrockguide
 KidsClick!
 sunsite.berkeley.edu/KidsClick!
 Kid’s Search Tools
 www.rcls.org/ksearch.htm
 Learning Page
 learningpage.com
 Pedagonet
 www.pedagonet.com
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Search Tools for Education
 Sites for Teachers
 www.sitesforteachers.com
 STEM-NET Theme Pages for Elementary
Students and Teachers
 www.stemnet.nf.ca/CITE/themes.html
 The Educator’s Reference Desk
 www.eduref.org
 The Gateway to Educational Materials (GEM)
 www.thegateway.org
 Yahooligans
 www.yahooligans.com
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