Transcript The Internet and the World Wide Web

The Internet and the
World Wide Web
The Internet
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Millions of Computers all around the world
No one person, company, or entity owns or
controls the Internet.
The Internet’s Hardware
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Owned or Shared by thousands of private
and public organizations
Supercomputers called NAPs (Network
Access Points), that serve as major hubs.
NAPs are connect to each other and to
Regional Routers through the largest lines of
the Internet call “Backbones”
Regional Routers are connect to Regional
Networks
The Internet’s Hardware
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Regional Networks connect to the various
ISP.
How do you connect to the internet from home?
Computers on the Internet
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Request Data
Provide Data
Help Send Data Along the Network
Computers on the Internet
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Your personal computer at your house is
an example of a computer that primarily
requests data, called a Client.
Computers that provide data are called
Servers, since they “Serve” data to other
computers.
Computers that help information travel across
the Internet are called Routers.
Every time data takes a turn on the Internet,
a Router is there to send it in the right
direction.
The Internet
Services on the Internet
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Voice Over IP (Internet Protocol)
Online Muli-Player Gaming
Internet Relay Chat(IRC)
Services on the Internet
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Peer to Peer File Sharing
Video Conferencing
Electronic Mail (e-mail)
Services on the Internet
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FTP (File Transfer Protocol)
World Wide Web
How the WWW Works
http:// - This is a “Protocol Prefix” that designates the file being
requested as accessible via Hypertext Transfer Protocol.
www - designates a requested file as World Wide Web document,
originally needed to distinguish between Web files and other Internet
files, this is often no longer needed. For example, you can go to
edulaunch’s web site by typing http://www. edulaunch.com or just
http:// edulaunch.com
edulaunch - Domain name that points to the server computer of the
edulaunch web site.
.com – Domain Name Extension designated for web sites with a
commercial focus
student_showcase - Directory or folder within which the web page
being requested is located.
bachelor_bet.html - This is the name of the exact file requested. You
may be wondering: What is the purpose of slashes? They signify that
you are moving deeper within the web site by entering a new folder or
directory. For example, the bachelor_bet.html file is inside the student
showcase directory.
How the WWW Works
Domain Name Extensions
The ending three-letter suffix of all top level
domains are to designate what type of web
site it is. Listed below are some of the most
common domain extensions.
.com
Country Code Extensions
There are now over 200 two-letter country code extensions. These
designate a web site as originating from a certain country. For
example, the web address of the London's famous metropolitan police Scotland Yard is http://www.met.police.uk Notice the two-letter
country code at the end(.uk).
A few examples of Country Code Extensions are listed below.
commercial use
.ar
.edu
Argentina
.il
Israel
.pr
Puerto
Ric
o
education and research
.gov
governmental agencies
.mil
military agencies
.br
Brazil
.in
India
.ru
Russian
Fed
erat
ion
.cn
China
.it
Italy
.tw
Taiwan
.uk
United
Kin
gdo
m
.us
United
Stat
es
South
.net
networks or ISPs
.org
non-profit organizations
.es
Spain
.kr
.ie
Ireland
.mx
Kor
ea
Mexico
Searching the Web
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Two Types of Web Searches
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Directories
Search Engines
Search Engines
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Method of searching that uses software
programs to search the web and record
information.
Programs
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Spiders
Robots
Crawlers
Intelligent Agents
Search Engines
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All the Web
Alta Vista
Ask Jeeves
Google
HotBot
Lycos
Wise Nut
www.alltheweb.com
www.altavista.com
www.ask.com
www.google.com
www.hotbot.com
www.lycos.com
www.wisenut.com
How a Search Engine Works
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Enter Your Request
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(Called a Query)
Request Compares it to the Search Engine
(Database)
Search Engine Delivers List based on
relevancy.
How Google Works
Information found on Google Inc.
Directories
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Directory-based searches use people to
search the web for similar web sites, they
then place them in a directory.
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Most Popular Directory-Based Search Engine
www.yahoo.com
Directories
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Directory-based searches use people to
search the web for similar web sites, they
then place them in a directory.
Getting the Whole Story?
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Web searches only a cover around 20-40%
of the web. Much of the content on the web is
hidden through password protected sites,
firewalls, Flash™ sites, databases, and other
things that search engines can’t read.
Boolean Searching
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Most People Just Type What They are
Looking For
Best Way to Search the Web
Allows the Search to be More Specific
Boolean Searching
Boolean Operative What it Does
Example
and (+)
Retrieves only pages that
include all the keywords.
Michael and Jordan,
Michael + Jordan
or
Retrieves pages containing Texas or Austin
any or all keywords.
and not (-)
Retrieves pages containing Michael an not Jordan,
one keyword but not the
Michael -Jordan
other.
Boolean Searching
Boolean Operative What it Does
Example
Phrase Searching
Only retrieve documents
where specified words
appear in order, side by
side..
"Remember the Alamo"
Plurals
If you want to search for
only the plural of a word
you must type in in plural.
Concerts
Capitals
If you want to search for
the capitalized version of
the word you should type
the whole word in CAPS.
ROCKETS
Boolean Searching
Boolean Operative What it Does
Example
Title Searching
Searching only for web
page titles.
+title:"Apostle Paul"
Domain Searching
Searching for a specific
web address within a
domain
+domain:.com
Host Searching
Searching a host for a
specific page.
+host:www.ford.com
Boolean Searching
Boolean Operative What it Does
Example
URL Searching
Searching web pages
where the keyword
appears in the URL or the
web site address.
+url:cars
Link Searching
Finding what web sites are
linked to a specific site.
link:www.ford.com
Web Searching Activities
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Taken Over Common Research Tools
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Dictionary
Thesaurus
Replaced Trips to the Library for Professional
Research
The Web has become the new phone book.
Web Searching Activities
You will complete two short Web search projects. First,
you will use the Web to make a personal phone
directory. The directory will contain the addresses
and phone numbers of family and friends along with
some helpful numbers from your local area. Second,
you will use the Web to plan a trip. Included will be
the route driven, the price and location of a rental
car, the price and location of a hotel at your vacation
destination and any stops or sights that will be taken
in along the way.
Activity 1 –
Making Your Own Phone Directory
The internet has many natural advantages over the
traditional phonebook. Some of those advantages
are:
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Internet directories contain the most current listings
available.
Internet directories have access to all the nations
telephone books.
Internet directories do not need storage space in your
home.
Using internet directories you may search an entire state at
once.
Activity 1 –
Making Your Own Phone Directory
In this activity you will construct your own
personal directory. Included will be phone
numbers and addresses of family members
and friends, local schools, restaurants, car
repair shops etc.
Activity 2 –
Planning Your Vacation on the Web
In this project you will use the internet to plan a fictitious car trip.
Conditions for the trip include:
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Your destination must be at least 600 miles from your school and no more
than 1200 miles
You will choose a hotel at your destination that costs less than $140 per
night.
You will find exact directions from your school to the hotel at your
destination.
You will find a mid-size car to rent with unlimited miles for at a cost of no
more than $500.00.
You will plan at least 2 activities at your destination and determine the cost
of each.
Your vacation will take place from June 1st to June 6th. You will need a six
night hotel stay and a car rental for 6 days.
Activity 2 –
Planning Your Vacation on the Web
In this project you will use the internet to plan a fictitious car trip.
Step One - Choose a Destination
Step Two - Choose Lodging at Your Destination
Step Three - Choose a Route
Step Four - Reserve Your Rental Car
Step Five - Plan Your Vacation Activities
Web Content
Who’s Behind the Web Page?
 Anyone can publish to the web
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No Laws to Monitor or Regulate its accuracy
Always a Good Idea to Double-Check all
information with a 2nd Source.
http://www.britannica.com/
Web Security
Internet security is a branch of computer
security specifically related to the Internet. Its
objective is to establish rules and measures
to use against attacks over the Internet.[1]
The Internet represents an insecure channel
for exchanging information leading to a high
risk of intrusion or fraud, such as phishing.[2]
Different methods have been used to protect
the transfer of data, including encryption.
Web Security
Web Tracking
 When a web site makes a record of your visit
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“Cookie” – A small text file that helps with web
tracking
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Cookies enable the web site to determine how often
you have:
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Visited Their Site
Date & Time of Your Last Visit
Specific Pages viewed on Site
Web Security
Web Tracking Example:
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Amazon.com, you may have seen a message on the site that
appears to be customized for you.
“Hello, we thought you might be interested in these CDs”, then
the CDs listed are all your favorites.
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A cookie by itself is not a bad thing. In fact they can make
surfing the web a richer experience and many well known
sites will not function properly without them.
Web Security
Advertising Spyware
 Advertising spyware is software installed on a
computer without the computer owner’s
knowledge or permission.
Web Security
Advertising Spyware
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Download Advertisements (Pop-Up Banners)
Identify Theft
Computer Damage
Web Security
Online Purchases & Encryption
 Shop From a Secure PC
 Shop Smart, and Only at Sites You Know
& Trust
 Shop with Your Credit Card
 Consider Alternative Payment Methods
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One-time use
Get a Handle on Spam
Web Security
Online Purchases & Encryption
 Encryption- Converts your text into gibberish
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File would need to be decrypt or translate it back
to original format
Majority of all reputable sites now offer encryption
services.
Look for the Lock Icon at the bottomw of the
browser window.
Encrypt your Own Files
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Use PGP (Pretty Good Privacy)
Web Security
Viruses
 A program designed to replicate and spread
to as many computers as possible.
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Immediately Visible
Working unseen on your computer for months
Web Security
Viruses
 Email Attachments
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DO NOT OPEN ANY FILE ATTACHMENT UNTIL
YOU HAVE CONFIREMD ITS ORIGIN
Even From a Friend – Viruses will over take
address books to spread itself.
Web Security
Viruses
 Trojan Horse
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Pretends to be something it is not, such as a
product update or a free software download.
Once you open it, the virus will begin to
execute its programming.
Keep Anti-Virus Software on your computer &
up to date.
The Future of the WWW
It will be almost impossible to predict what the Web will be like in the future. Ten years ago, few
people would have predicted the rapid growth of the web in size and content. There are
three things you can bet on.
1) More and more people will use the web. Not only is the world’s population increasing,
but computer prices keep falling. As the “computer generation” grows into adulthood,
replacing the "baby-boom" generation in the work force, web use will increase.
2) The Web will get faster and faster. Not too long ago, you would have been happy to
have a 28.8 Kilobytes per/sec modem. Then 56k modems came along. Now there is DSL
and Cable offering speeds over 1000k. Over 70% of high school students in suburbia
America already has a high speed connection. There is already talk about an Internet2,
bringing technology enabling everyone will have the speed that only today’s backbone lines
enjoy.
3) The Web will grow continually grow more wireless. Popping up all over the United States
are “hot spots”, areas where a business, school, or home is broadcasting their Internet
connection. All laptops are now equipped with Mobile Technology to automatically connect
to any wireless Internet signal it can find. Many restaurants are broadcasting a wireless
signal in an effort to attract more customers. Many predict that within a few years, you may
not need a wired connection at all.
The Internet and the
World Wide Web