Transcript Introduction to the Internet

Networks and the Internet
PCS115 Introduction to the Internet
©Richard L. Goldman
December 7, 2006
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What is a Network?
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Two or more computers connected together.
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A Network
Server
Network
Printer
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What is the purpose of a network?
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Allows people on the network to share information.
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Data files
Pictures
Music
?
Allows people on the network to share resources.
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Printers
Scanners
Programs
?
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Connection to the Internet
(Home Model)
Internet
Service
Provider
Personal Computer
(ISP)
Internet
Modem
Printer
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Connection to the Internet
(Business Model)
Server
Network
Internet
(ISP) Router
Printer
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What is the Internet?
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A large number of networks as well as
individual computers connected together.
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What is the World Wide Web?
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A system that allows people to easily
navigate through the Internet (using
hyperlinks) and view documents.
The WWW uses a computer language called
HTML that all computers can read.
HTML stands for:
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Hypertext Markup Language.
Developed at the CERN in 1989 by Timothy
Barners-Lee.
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What is a link (Hyperlink)?
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A link is an object (usually a word, phrase, or
picture) that contains the Internet address of
another location on the Internet.
When you click on the link it takes you there.
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What is a Web Page, a Web Site, Home
Page, and a Web Server?
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Web Page – A Hypertext document.
Web Site – A collection of web pages.
Home Page –
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The browser “Start Page”
A page about a person or organization
The first web page of a web site.
Web Server – The computer that holds web
sites.
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What are Newsgroups?
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Newsgroups are forums on specific topics
where comments or questions are posted.
Other people reading the comments or
questions may respond to them.
You may check back later to see what
responses you may have received.
Newsgroups are often very useful.
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What are Chat Rooms?
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Chat rooms are live discussion groups on the
Internet.
They may be started by anyone on any topic (or no
topic at all).
Any one may view or join in.
Some are moderated but many are not.
They are often strictly for entertainment.
Creditability is a major problem.
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What is an Internet Service Provider
(ISP)?
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A company that provides access to the
Internet through their computers.
Examples:
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America On Line (AOL) – national
Valley Internet Company – Local
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What is a Browser?
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A program on your computer that can retrieve
and display hypertext documents found on
the Internet.
Browsers:
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Microsoft;
Netscape;
Oracle;
Opera Software;
Internet Explorer
Navigator
Power Browser
Opera
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Home Page
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The page that appears when you start a
browser.
Can be set by:
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IE 4 – View/Internet Options/Home Page
IE 5 – Tools/Internet Options/Home Page
IE 6 – Same – Currently used by most Users
IE 7 – Click
button then select “Add or change
home page”
Can return to it at any time by clicking the
Home button on the Standard Toolbar.
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Toolbars (View menu/Toolbars)
IE 5
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Toolbars
Title Bar
Menu Bar
Standard ToolBar
Address Bar
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Toolbars
Links
Bar
Status Bar
Task Bar
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Title Bar
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Identifies active Web page.
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Menu Bar
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Access to commands and options.
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File
Edit
View
Go or
Favorites
Help
Tools
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Standard Toolbar
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Buttons for common commands.
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Back
Forward
Stop
Refresh
Home
Search
Favorites
History
Channels
Fullscreen
Mail
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Address Bar
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Contains an Address Box to enter the
address of the Web page that you want to
view.
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Links Bar
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A place to put links to your favorite sites.
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Status Bar
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Shows:
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Target of link
Status of Search and load activity
Progress of page completion (Progress Bar)
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URL
Uniform Resource Locator
http:// www.northern.edu/data/programs.html
Protocol:
http = Hypertext Transfer
Protocol
Used to transfer html documents.
ftp = File Transfer Protocol
Used to transfer whole files.
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URL
Uniform Resource Locator
http:// www.northern.edu/data/programs.html
Server Address:
Name of computer (including the
Domain Name Type code) that
contains the data you are seeking.
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URL
Uniform Resource Locator
http:// www.northern.edu/data/programs.html
Domain Types (or Top Level Domains):
The original 7 U.S. Internet Domain types.
edu
education
com
commercial
org
nonprofit organizations
gov
government
net
network host or gateway orgs
int
Internet organizations
mil
military
Two letter country codes are used outside of the
United States.
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URL
Uniform Resource Locator
http:// www.northern.edu/data/programs.html
Folder (subweb or subdirectory):
The folder on the server that
contains the file that you are
looking for.
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URL
Uniform Resource Locator
http:// www.northern.edu/data/programs.html
File Name:
The name of the file.
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URL’s
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Most URL’s are lower case, however some
contain Upper case letters.
URL’s may be case sensitive and must be
typed in without deviation.
Redirection, automatic forwarding, and other
techniques allow some variation on popular
sites.
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DNS – Domain Name Server
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Converts:
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URL (Universal Resource Locator) into
DDNS (Dotted Decimal Number System) (IP address)
www.northern.edu = 129.70.5.101
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Printing
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Screen size and page size don’t match. The
browser may adjust content to fit the page.
Select what you want and print the Selection.
Select and copy what you want and paste it into
a word processor. Edit it and print it from there.
Use Adobe Acrobat Reader files (.PDF) if
available.
Laser printed pages usually cost 1-3 cents per
page.
Bubble jet printed pages usually cost 7-15 cents
per page.
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Help
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Contents
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Index (Key words)
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Like the table of contents of a book. It shows you a view of
the topics covered in Help.
Like the index of a book, just type in the word you are
looking for.
Search
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Gives you the ability to search for any word that might
appear in the Help documentation.
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