Transcript Shelly Cashman Series Discovering Computers A Link to the

Teachers Discovering Computers
Integrating Technology
in the Classroom
3rd Edition
Chapter 2
Communications, Networks, the Internet,
and the World Wide Web
CHAPTER 2 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
2
CHAPTER 2 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
3
CHAPTER 2 OBJECTIVES
Identify several types of multimedia
products available on the Web
Explain how Internet services such as email, 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
4
WHAT IS COMMUNICATIONS?
A process in which two or more
computers or devices transfer data,
instructions, and information
Sometimes called telecommunications
5
WHAT IS COMMUNICATIONS?
 Electronic mail (e-mail)
 Voice mail
 Fax (facsimile)
 Telecommuting
 Online services
 Videoconferencing
 Internet
 World Wide Web
6
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
7
A COMMUNICATIONS SYSTEM
8
COMMUNICATIONS
NETWORKS
Communications
channel
• Transmissions media
– Twisted-pair cable
9
COMMUNICATIONS
NETWORKS
• Digital vs. analog
signals
– Modem
– External modem
– Internal modem
– Network interface
cards
10
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
11
COMMUNICATIONS
NETWORKS
Home Networks
• Connects multiple
computers in your
home
• Share Internet
access and
resources
12
NETWORKING THE
CLASSROOM, SCHOOL, AND
DISTRICT
School network
server
Example
classroom
• Three Macintosh
computers
• Printer
13
NETWORKING THE
CLASSROOM, SCHOOL, AND
DISTRICT
Example school network
• Classrooms
• Administration
• Computer lab
Example school district
• Central office
• Various schools
14
SCHOOL’S LOCAL AREA
NETWORK
15
DISTRICT’S WIDE AREA
NETWORK
16
WIRELESS SCHOOLS AND
CLASSROOMS
 Keep in touch with
family and friends from
anywhere
•
•
•
•
Smart pagers
Cellular telephones
Handheld computers
Notebook computers
 Wireless technology
brings the computer lab
to students
17
HIGH SPEED OR
BROADBAND ACCESS
Government works to provide high
speed Internet access to classrooms
Broadband technology transmits signals
at much faster speeds
18
THE BENEFITS OF COMPUTER
NETWORKS IN EDUCATION
 Sharing of computer
hardware, software, and
data resources
 Unlimited educational
resources
 Communicate with other
educators and students
19
WHAT IS THE INTERNET?
Worldwide group of connected networks
that allow public access to information
and services
No single organization owns or controls
Estimated 500 million users
Variety of uses
20
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.
21
HISTORY OF THE INTERNET
Started as a network of four computers
at in both California and Utah in 1969
Advanced Research Projects Agency
(ARPA) - ARPANET
More than 35 million computers today
Backbone first provided by National
Science Foundation (NSF) - NSFnet
22
HISTORY OF THE INTERNET
23
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
24
HOW THE INTERNET WORKS
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
25
26
HOW THE INTERNET WORKS
Internet Service Providers versus
Online Service Providers
• Have permanent connections to the
Internet
• Provide temporary connections to
individuals and companies for a fee
• Local and national ISPs
• Online service providers offer members
only areas
27
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)
28
29
HOW THE INTERNET WORKS
The Internet Backbone
• Acts as a highway
• Local ISPs connect through leased lines
to national ISPs
30
31
HOW THE INTERNET WORKS
Internet Addresses
• Numeric addresses
• Domain name
– Domain type abbreviations
– Country code abbreviations
32
33
THE WORLD WIDE WEB
(WWW)
Started in the early 1990s
Hyperlinks
Uniform Resource Locator (URL)
Hypertext transfer protocol
34
THE WORLD WIDE WEB
(WWW)
35
THE WORLD WIDE WEB
(WWW)
How a Web Page
Works
• Hypertext
• Hyperlinks
– Target
– Relative
– Absolute
36
THE WORLD WIDE WEB
(WWW)
•
•
•
•
•
Discovery learning
Web Surfing
Webmaster
Hypertext markup language (HTML)
Web publishing
37
THE WORLD WIDE WEB
(WWW)
Web Browser
Software
• Interprets HTML and
displays Web pages
and enables you to
link to other Web
pages and Web sites
38
THE WORLD WIDE WEB
(WWW)
Web Browser
Software
• Mosaic
• Netscape Navigator
• Microsoft Internet
Explorer
39
THE WORLD WIDE WEB
(WWW)
Searching for
Information on the
Web
• Directory maintained
by a search engine
company
• Helps find information
on the Web
• Search engine
• Subject directory
40
THE WORLD WIDE WEB
(WWW)
Multimedia on the
Web
• Web pages
incorporate
graphics,
animation, audio,
video, and virtual
reality
• Plug-ins
41
THE WORLD WIDE WEB
(WWW)
Multimedia on the
Web
• Graphics
– Used to enhance
text-based Internet
42
THE WORLD WIDE WEB
(WWW)
Multimedia on the Web
• Graphics
– Graphics formats
43
THE WORLD WIDE WEB
(WWW)
Multimedia on the
Web
• Graphics
– Thumbnails
44
THE WORLD WIDE WEB
(WWW)
Multimedia on the Web
• Animation
– Marquees
– Animated GIFs
45
THE WORLD WIDE WEB
(WWW)
Multimedia on the Web
• Audio
– MP3 format
– MP3 player
– Streaming audio
– RealAudio
46
THE WORLD WIDE WEB
(WWW)
Multimedia on the
Web
• Video
– Streaming video
– RealVideo
47
THE WORLD WIDE WEB
(WWW)
Multimedia on the Web
• Virtual Reality
– Simulation of real or imagined
environment that appears as a threedimensional (3-D) space
– VR worlds
48
This instructional Web site uses VR to teach biology students
49
about cells and body tissues.
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
50
OTHER INTERNET SERVICES
FTP (file transfer
protocol)
• FTP sites and
servers
• Allows file downloads
and uploads
• Anonymous FTP
• FTP programs
51
OTHER INTERNET SERVICES
Newsgroups and Message Boards
• Newsgroup – online area in which users
conduct written discussions about a
particular subject
– Usenet
•
•
•
•
•
News server
News reader
Article
Posting
Threaded discussion
52
OTHER INTERNET SERVICES
Newsgroups and Message Boards
• Message Boards – easier to use than
newsgroups
53
OTHER INTERNET SERVICES
Mailing Lists
• Group of e-mail names and addresses
given a single name
• Subscribing and unsubscribing
• LISTSERVs
54
OTHER INTERNET SERVICES
Chat Rooms
• Real-time conversation
• Chat rooms
• Chat clients
– IRC (Internet relay chat)
– Microsoft Chat
55
56
OTHER INTERNET SERVICES
 Instant Messaging
• See when one or more
people are online
• Exchange messages and
files
• Join a private chat room
 Short Message Service
(SMS)
• Send and receive text
messages from Webenabled devices
57
NETIQUETTE
Internet etiquette
• The code of acceptable behaviors
users should follow while on the
Internet
58
59
INTERNET SECURITY
Firewall
Filtering software
Acceptable Use Policy (AUP)
60
THE IMPACT OF THE
INTERNET AND THE WORLD
WIDE WEB ON EDUCATION
The Web is the Gutenberg press of
modern times
Collaboration with other teachers and
students
• ePALS
New instructional strategies
61
62
THE FUTURE OF THE
INTERNET AND THE WORLD
WIDE WEB
Will connect 80 percent of the world’s
computers in a few years
More than a billion wireless communication
devices will be in use by the middle of the
decade
All K-12 teachers will have access to the
Internet in their classrooms
Wireless technology will become
commonplace in K-12 education
63
THE FUTURE OF THE
INTERNET AND THE WORLD
WIDE WEB
Everyday appliances with embedded
computers will have Internet access
More intelligent and focused Web
search capabilities
100 to 1,000 times faster in a few years
Business will continue to be the driving
force
64
THE FUTURE OF THE
INTERNET AND THE WORLD
WIDE WEB
Increased access speeds and greater
availability will allow teachers and
students to view thousands of videos
The Web will become an integral part of
all education and will revolutionize the
way students learn core subjects
65
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
66
CHAPTER SUMMARY
Describe the World Wide Web portion
of the Internet
Specify how Web documents are
linked to one another
Explain the use of browser software
Explain how to use a Web search tool
to find information
67
CHAPTER SUMMARY
Identify several types of multimedia
products available on the Web
Explain how Internet services, such as email, newsgroups, chat rooms, and instant
messaging work
Describe the educational implications of the
Internet and the World Wide Web
Describe how to connect to the Internet and
the World Wide Web
68
Teachers Discovering Computers
Integrating Technology
in the Classroom
3rd Edition
Chapter 2 Complete
70
An extensive, current list of Web sites in various categories
can be found at: http://www.scsite.com/tdc3
Click the Special Feature, Guide to WWW Sites link on the
left sidebar
71
USING A SUBJECT
DIRECTORY
Provides categorized lists of links
Arranged by subjects
This example will show you how to find
information on Mark Twain’s childhood
72
USING A SUBJECT
DIRECTORY
Start your browser and enter
the URL www.yahoo.com
in the Address box. When
the Yahoo! home page
appears, point to the
Literature link below Arts &
Humanities. You point to
Literature because that is the
category in which Mark
Twain made his
contributions.
73
USING A SUBJECT
DIRECTORY
Click Literature. When the
Literature page appears,
point to the Authors link.
You point to Authors
because Mark Twain was an
author. Each time you click
a category link, you move
closer to the topic.
74
USING A SUBJECT
DIRECTORY
Click Authors. When the
Authors page appears, scroll
down and point to the letter
T in the alphabetical site
listings. (You can also find
information about Mark
Twain by clicking the
Literary Fiction link.)
75
USING A SUBJECT
DIRECTORY
Click the letter T. The
browser window displays an
alphabetical listing of
authors whose last names
begin with T, as well as
other author-related
organizations that begin with
T. Scroll down and then
point to the Twain, Mark
(1835-1910) link.
76
USING A SUBJECT
DIRECTORY
Click Twain, Mark (18351910). When the page
appears, scroll down and
then point to the Mark
Twain Papers & Project link.
77
USING A SUBJECT
DIRECTORY
Click the Mark Twain
Papers & Projects link.
When the page appears,
click the links one at a time.
Use the browser’s Back
button to Return to The
Mark Twain Papers &
Project page after viewing
the page associated with
each link.
78
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, mark
twain papers
79
USING A SEARCH ENGINE
Start your browser and then
enter the URL
http://www.google.com
in the Address box. When
the Google home page
appears, type mark twain
papers in the Search text
box and then point to the
Google Search button.
80
USING A SEARCH ENGINE
Click the Google Search
button. When the results of
the search appear, scroll
through the links and read
the descriptions. Point to
the Mark Twain Papers &
Project link.
81
USING A SEARCH ENGINE
• Click the Mark Twain
Papers & Project
link. A Web page
appears that
contains extensive
information about
the collected original
documents by and
about Mark Twain
82
LIMITING THE SEARCH
83
GUIDELINES TO SUCCESSFUL
SEARCHING
Use nouns as keywords, and put the
most important terms first in your
keyword
Use the asterisk (*) to find plurals of
words
Type keywords in lowercase to find both
lowercase and uppercase variations
84
GUIDELINES TO SUCCESSFUL
SEARCHING
Use quotation marks to create phrases
so the search engine finds the exact
sequence of words
Use a hyphen alternative
• E-mail or email
Limit the search by language
Use uppercase characters for Boolean
operators
85
GUIDELINES TO SUCCESSFUL
SEARCHING
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
86
POPULAR SEARCH SITES
Google
• google.com
AllTheWeb
• alltheweb.com
Yahoo!
• yahoo.com
MSN Search
• search.msn.com
AOL Search
• search.aol.com
87
POPULAR PORTALS
Ask Jeeves
• askjeeves.com
HotBot
• hotbot.com
Lycos
• lycos.com
LookSmart
• looksmart.com
AltaVista
• altavista.com
88
POPULAR PORTALS
Netscape Search
• search.netscape.com
Overture
• overture.com
InfoSpace
• infospace.com
89
POPULAR EDUCATION
SEARCH TOOLS
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’ Web Site K-12
• www.ceismc.gatech.edu/busyt
90
POPULAR EDUCATION
SEARCH TOOLS
Education Index
• educationindex.com
Education World
• www.education-world.com
EduHound
• www.eduhound.com
emTech
• www.emtech.net
FirstGov for Kids
• kids.gov
91
POPULAR EDUCATION
SEARCH TOOLS
Great Web Sites for Kids
• www.ala.org/alsc/children_links.html
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
92
POPULAR EDUCATION
SEARCH TOOLS
Sites for Teachers
• www.sitesforteachers.com
STEM-NET Theme Pages for Elementary
Students and Teachers
• www.stemnet.nf.ca/CUTE/themes.html
The Gateway to Educational Materials (GEM)
• www.thegateway.org
TekMom’s Search Tools for Students
• tekmom.com/search
Yahooligans
• www.yahooligans.com
93