Transcript The Internet and World Wide Web

The Internet and World
Wide Web
Ilona Kane
The Internet

A worldwide collection of networks that links
millions of businesses, government agencies,
educational institutions, and individuals.

Internet’s Resources
– Access to information and research
– Communicate with others around the world
– Bank, Shop, Download music and movies
– Access other computers and exchange files
History of the Internet

Started by the Pentagon’s networking
project known as the Advanced
Research Projects Agency (ARPA)

ARPA is an agency of the U.S.
Department of Defense whose goal
was to create a network that:

ARPA underwent phenomenal
growth as researchers realized the
great benefit to sharing information

In 1986, the National Science
Foundation, (NSF) connected its
huge network of five supercomputer
centers, called NSFnet to
ARPANET forming the complex
networks and hosts known as the
Internet today

The Internet traffic today is handled
by a variety of corporations and
commercial firms, who along with
telephone, cable, and satellite
companies contribute to the internal
structure of the internet.
– Allowed scientists at different
locations to share information and
work together on military and
scientific projects
– Could function even if part of the
network were disabled or destroyed
by a disaster such as a nuclear attack

This network is known as the
ARPANET
How the Internet Works

Internet Service Providers
– Is a business that has a permanent Internet
connection and offers temporary connections
to individuals and companies free or for a fee
– 2 major types:



Regional ISP- provides access to the
Internet through one or more telephone
numbers local to a specific geographic
area
National ISP- a larger business that
provides local telephone numbers in
major cities and towns nationwide
Online Service provider- supplies Internet
access, but has many members-only features that
offer a variety of special content and services
such as weather, games, and travel guides

Wireless Service Provider- provides
wireless Internet access to users with wireless
modems or Web-enabled computer devices
Connecting to the Internet
1.
Dial-up access
1.
2.
3.
2.
Digital Subscriber Line (DSL)
1.
3.
Provides an easy and inexpensive way for users to
connect to the Internet
Uses a computer, a modem, and a regular telephone
line to dial into an ISP or OSP
Slow-speed technology
Provides high-speed connections over a regular
copper telephone line
Cable Modem
1.
2.
Provides high-speed Internet connections through the
cable television network
Along with DSL costs 2xs as much as dial-up
How Data Travels
the Internet



Connection to the Internet is a
transfer of data around the world
using servers and clients
Server- computer that manages
the resources on a network and
provides a central storage area
for resources such as programs
and data
Client- a computer that can
access the contents of the
storage area on a server
Internet Addresses



IP Address- (Internet Protocol
Address) is a number that
uniquely identifies each
computer or device connected
to the Internet
Domain name- the text version
of an IP address
DNS server- translates the
domain name into its associated
IP address, so data can route to
the correct computer
The World Wide Web

Consists of a worldwide
collection of electronic
documents, also known as
Web pages

A collection of related
Web pages- Web Site
Browsing the Web

Web browser- a software program that allows
you to access and view Web pages
– Most widely used:



Microsoft Internet Explorer
Netscape
Home page- starting page for a browser
– Provides information about the Web site’s purpose and
content

Hyperlink- (link) a built-in connection to another
related Web page or part of a web page
Uniform Resource Locator

Is a Web page’s unique address
– Tells the browser where to locate the document
– Makes it possible for you to navigate using links

Typical URL:
http://www.lasalle.edu/students/home.htm
– http = protcol
– www.lasalle.edu = domain name
– /students/home.htm = path
Search Engines

Is a software program you
can use to find Web sites,
Web pages, and Internet
files
– Are specifically useful
when the exact URL is not
known
– Common Search Engines
include:


Dogpile, Excite, Yahoo,
Google, Lycos
Sources: dogpile.com,
excite.com, yahoo.com,
google.com, lycos.com
Types of Web Pages
1. Portal Web Page- offers a variety of Internet
services from a single convenient location
1.
2.
3.
4.
5.
6.
Offer search engine
News reports
Weather
Personalized web pages
Email
Chat rooms
2. News Web Page- contains news worthy
material including stories and articles relating
to current events, life, money, and sports
More Web Pages
3. Informational Web Page- contains factual
information such as census data, tax codes, published
research findings
4. Business/Marketing Web Page- contains content
that promotes or sells products or services
–
Such companies include: AT&T, and the Disney Co.
5. Advocacy Page- acts as a device to convince the reader
of the validity of the content that describes a cause,
opinion, or idea
6. Personal Web Page- established by a private individual
who normally is not associated with any organization
–
To use for job hunting or to share life experiences
Multimedia on the Web
Any application that integrates texts with one or
more of the following elements: graphics,
sound, video, and virtual reality
 Graphics- a digital representation of
information such as a drawing, chart, or
photograph

Animation- the appearance of motion
created by displaying a series of still
images in a rapid sequence
– Makes pages more visually interesting
and draws attention

Audio- music, speech, or any other
sounds
– MP3 is a popular technology that
compresses audio
– Streaming- the process of transferring
data in a continuous and even flow

Important because most users do not have
a fast enough Internet connection
More Multimedia
•
Video- images that are played back at various
speeds
– Consist of individual video files, such as movies or TV
clips, that you download
– Web cam- a video camera whose output displays on a
Web page
•
Virtual Reality- the use of computers to simulate
a real or imagined environment that appears as a
3D space
– Often used for scientific models, architectural layouts,
and games
Webcasting

Pull Technology

Push Technology
1. a server automatically
downloads content to your
information which relies
computer at regular intervals
on a client such as your
or whenever updates are
computer to request a Web
made to the site
page from a server
2. Example: current sporting
2. Example: enter a URL or
event scores displayed on
click a link
your desktop
1. Method of obtaining
Webcasting – uses pull technology, push technology and/or
streaming media to deliver information at regualr intervals
without you having to request it, or to deliver live recorded
sound and video broadcast to your computer
Creating a Web Site

Web page authorizing
–
Involves working on the computer to
compose the Web site
1.
2.
Word processing packages help create basic
web pages that contain text and graphics
Web page authorizing software
 Is specifically to help create a web page
 Used to create more sophisticated web pages
that include animation, video, and sound
3.
When using a word processing or Web page
authorizing software, the Web page is saved in
Hypertext Markup Language (HTML)
 Is a set of special codes that format a file for
use on a web page
Deploying and Maintaining a
Web Site

Store a created Web page on a Web server
– Many ISPs and OSPs provide their customers with a
Web address and storage space for the Web site
– Web hosting Services- provide storage for your Web
site for a monthly fee

Upload the Web site- copy it from your computer
to the Web server
 Submission Service- a Web-based business that
offers a registration package in which you pay to
register with hundreds of search engines
 Webmaster- the individual responsible for
maintaining a Web site and developing Web pages
E-mail





The transmission of messages and files via a
computer network
One of the original services of the Internet
Email address- combination of user name and
domain name that identifies a user
Address Book- program in email that a contains a
list of names and email addresses
Mailbox- a storage location usually residing on
the computer that connects you to the Internet
Web-based Groups

Message Board- type of discussion group, also
known as a discussion board

Mailing Lists- a group of e-mail names and addresses

Chat rooms- a location on the Internet server that
allows a real-time conversation to take place on a
computer

Instant Messaging- a real-time Internet
communications service that notifies you when one or
more people are online and allows you to exchange
messages or files
Sources

Discovering Computers 2003
 Web sites– Aol.com
– Dogpile.com
– Excite.com
– Google.com
– Lycos.com
– Msn.com
– Yahoo.com