CHAPTER 1- INTERNET & WORLD WIDE WEB

lynxfatkidneyedNetworking and Communications

Oct 26, 2013 (3 years and 9 months ago)

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CHAPTER 1
-

INTERNET & WORLD WIDE WEB

In 1969, the US Department of Defense started a project to allow researchers and military
personnel to communicate with each other in an emergency. The project was called
ARPAnet
and it is the foundation of the
Internet
.

Throughout the 1970's, what would later become the Internet was developed. While mostly
military personnel and scientists used it in its early days, the advent of the
World Wide Web

in the early 1990's changed all that.

Today, the Internet is n
ot owned or operated by any one entity. This worldwide computer
network allows people to communicate and exchange information in new ways.

What is Internet?

The Internet is the largest
computer network
in the world, connecting millions of computers.
A
netw
ork

is a group of two or more computer systems linked together.

T
here are two types of computer networks:

1.

Local Area Network (LAN)
: A LAN is two or more connected computers sharing
certain resources in a relatively small geographic location (the same buil
ding, for
example).

2.

Wide Area Network (WAN)
: A WAN typically consists of 2 or more LANs. The
computers are farther apart and are linked by telephone lines, dedicated telephone
lines, or radio waves. The
Internet

is the largest Wide Area Network (WAN) in
existence.

Servers

All
computers on the Internet
(a wide area network, or WAN) can be lumped into two
groups: servers and clients. In a network,
clients

and
servers

communicate with one another.

A server is the
common source that



Provides shared services

(for example, network security measures) with other
machines.



Manages resources
(for example, one printer many people use) in a network.

The term server is often used to describe the
hardware

(computer), but t
he term also refers
to the
software

(application) running on the computer. Many servers are
dedicated
, meaning
they only perform specific tasks.

For example,



An email server is a computer that has software running on it allowing it to "serve"
email
-
related services.



A web server has software running on it that allows it to "serve" web
-
related services.

Clients

Remember, all
computers on the Internet

(a wide a
rea network, or WAN) can be lumped
into two groups:
servers

and
clients
, which communicate with one another.

Independent computers connected to a server

are called
clients
. Most likely, your home
or office computer does not provide services to other compu
ters. Therefore, it is a
client
.

Clients run
multiple client software applications

that perform
specific functions
.

For example,



An email application such as Microsoft Outlook is client software.



Your web browser (such as Internet Explorer or Netscape) i
s client software.

Servers and Clients Communicate



Your computer (client hardware) is running a web browser such as Internet Explorer
(client software).



When you want to surf the web, your browser connects to a remote server and requests
a web page.



The

remote server (server hardware) runs web server software (server software).



The web server sends the web page to your computer's web browser.



Your web browser displays the page.

How is the Internet Used?

As the Internet has grown, it has developed into a multifaceted tool with a vast range of uses.
It's now easy to
keep in touch with friends
, publish your own
articles
, or even watch your
favorite
TV shows

using the Internet.

Ways how the Internet is used t
oday



BLOG



is a short for “web log”. It is a type of web site that is usually updated
frequently, often with news articles or random thoughts. Some sites, such as
blogger.com, allow you to create and edit your blog for free.



E
-
MAIL



short for ‘electronic

mail” is a system for sending and receiving messages
online. Many e
-
mail services include extra feature such as calendars, task lists, instant
messaging, web feeds, and news headlines.



FTP

-

FTP stands for File Transfer Protocol. This is both a program a
nd the method used
to transfer files between computers. Anonymous FTP is an option that allows users to
transfer files from thousands of host computers on the Internet to their personal
computer account. FTP sites contain books, articles, software, games,
images, sounds,
multimedia, course work, data sets, and more.



INSTANT MESSAGING



Instant messaging programs allow you to have
conversations with your friends or just write them a quick note.



MAILING LIST

-

is a group of people with shared interest. Their

e
-
mail addresses are
collected into group, and this group is identified by a single name. Whenever you send
a message, everyone on the list receives a copy. Some mailing list are called
LISTSERVs, named after a mailing list software program. Many profe
ssional groups and
associations utilize mailing lists as an effective way of communicating with the members
and potential members.



NEWSGROUP AND BULLETIN BOARDS

-

a newsgroup is a discussion forum or type
of bulletin board. Each board is dedicated to a
discussion on a particular topic. The
difference between a newsgroup and a mailing list is that with a news group you can
select the topics you want to read. These messages are stored on a news server, which
is a computer that contains the necessary newsgr
oup.



ONLINE CHAT



is a system that allows users to communicate in real time. Unlike e
-
mail, all messages show up immediately in the same window, which makes
conversations quicker and easier. Instant messaging is a type of chat where you
communicate with a

specific person instead of an entire chat room.



ONLINE CONFERENCING

-

Provides user to chat with audio and video. Online
conferencing requires microphone and speakers for audio and digitizing camera for
video.



PODCAST



basically a web feed for media. Wit
h a podcast, you can subscribe to a
series of audio or video files that will automatically be downloaded to your computer.
The files can then be played on the computer or mp3 player.



SOCIAL BOOKMARKING



allows users all over the Internet to share and rate

interesting sites. Typically, the sites will then be ranked based on popularity or rating,
-
making it easier for users to find web sites that have a lot of “buzz”. Examples include
Digg, Delicious, and Reddit.



SOCIAL NETWORKING


refers to online service
s that allow people to interact with
each other and stay connected with friends and family. Examples include Facebook,
Friendster, and Twitter.



STREAMING



If you watch a movie online or listen to iTunes radio, it’s called
streaming media, which means it d
ownloads while it’s playing so you don’t have to wait
for it to download first.



VOIP



Voice over Internet Protocol (VoIP), also known as Internet Telephone, allows a
user to have telephone service through an internet connection. Some people find that
the
y can save money by using VoIP instead of purchasing a separate telephone service.
One example is Skype.



WIKI


is a type of web site that allows content to be edited or created by anyone. This
allows content to stay up to date and allows errors to be foun
d and corrected. Examples
include Wikipedia, which is an ancyclopedia, and wikiHow, which is a collection of how
-
to.


What is World Wide Web?

Important Web Terms



WWW

-

Also called the Web or World Wide Web. The
World Wide Web

is a
virtual
network

of
web
sites

connected by
hyperlinks

(or
"links"
). Web sites are stored on
servers

on the Internet, so the World Wide Web is a part of the Internet.



Web Browser

-

A piece of software used to navigate the Web. Internet Explorer and
Netscape are web browsers.



GUI (Graphical User Interface)
-

A GUI takes advantage of your computer's graphics
(picture) capabilities to increase ease of use. For example, the buttons you point and
click to surf the web is part of your web browser's GUI . Most operating systems inclu
de
a GUI, such as Windows and Mac OS. In the past, there was no pointing and clicking;
rather, the user had to know a command language to operate the computer.



HTML (Hypertext Markup Language)

-

The formatting language used to create web
documents.



Hypert
ext
-

The system of electronically linking words or pictures to other words or
pictures.



URL (Uniform Resource Locator)

-

Each web page has its own address on the
Internet, which is called a URL. To recognize one another over the Internet, computers
conve
rt human
-
friendly addresses like www.gcflearnfree.org to numerical
IP
addresses
. You may type in either 216.119.102.26 (GCFLearnFree.org's IP address) or
www.gcflearnfree.org (our human
-
friendly domain name) to get the homepage.



HTTP (Hypertext Transfer P
rotocol)

-

You may have noticed the
http://

preceding
URLs. For example: http://www.gcflearnfree.org. The first part of the URL, usually
HTTP
, indicates the file type. HTTP, the system for transferring web documents, defines
how messages are formatted and
transmitted over the Internet.

What is a modem?



A
modem

is a device that
converts

a computer's
outgoing data

to a format that can
be transferred via telephone lines. Modems can also convert
incoming data

so the
computer can read it.



A modem can be locate
d inside or outside your computer. Some of the different types of
modems are internal, external, voice/data, and fax modems.

What is a Web browser?



Web browser is a software used to navigate the Web.




Internet Explorer

and
Netscape

are examples of web brow
sers.

Internet Service Providers

Internet Service Providers (ISPs)

are
companies

that provide access to the Internet.

For a monthly fee (and an initial activation fee), you can purchase a
software package

from
your ISP. These packages feature different levels of Internet access. Flat
-
rate service will buy
you unlimited hours, whereas a less
-
expensive hourly package buys limited Internet access. In
either case, the speed with which you access the Internet f
actors into how much you pay per
month.

The ISP software package usually includes:



Username
. A unique name used to gain access to a computer system.



Password
. A combination of keyboard characters. Used in combination with a
username, passwords allow acces
s to restricted computer information. It is important to
keep passwords secret.



Access phone number
. For example, (919) 555
-
5555.

If you connect to the Internet at work, you may be part of a LAN (local area network) that
shares network resources. To gain

Internet access, your employer contracted with an ISP.

Bandwidth

The Need for Speed

Slow Internet access means some users are unable to access certain web pages, especially
those loaded with graphics, sound, and video. So, to access the latest web techno
logies, users
need more speed.

In response to the need for speed,
modems (a device used to access the Internet)

were
built that were capable of faster
data transmission rates
.

Faster data transmission means



Faster web pages



Faster email services



Music, a
nimation, and video plays smoothly

Data Transmission Rates

At higher speeds, modems are measured in terms of
bits per second
(bps). A
bit

is a unit of
measurement that measures the transfer of data, or information. For example, if you have a
56K modem, you
r modem may be capable of transferring 56,000 bits per second.

Data Transmission Rates



Early 90's


o

19.2K bits per second

o

28.8K bits per second

o

33.6K bits per second



1998
-
Present


o

56K bits per second

o

Almost 10 Million bits per second (Asymmetric Digital Subscriber Line, (ADSL),
Cable modems)

What is Bandwidth?

A fast modem doesn't ensure fast transmission rates. Fast data transmission often depends on
bandwidth
.

Bandwidth
is the
amount of data
actually being sent through a network circuit
.

Example: Think of bandwidth in terms of the road system.

Let's say you want to estimate the time it takes for you to commute from home to work. You
have to travel through a physical network of roadways to t
ravel from home to work.

To estimate your commute, consider



What is the speed limit?



Where are you located (big city or rural setting?)



How big (wide) is the road? (2
-
lane roads, 4
-
lane roads, or a 6
-
lane interstate?)



How much traffic will be on the road
at any given time?



Is there any construction?

The Internet is similar to the roadway example.

Remember, the Internet is a physical
network (phone lines, etc
). Data has to travel through that physical network. Too much traffic
on the network means you may be unable to connect at a fast rate, or at all. The more open
and wider your network is, the faster you can connect and surf.

Challenge!





Go to
Yahoo.com
.



Using the search box, type in the words"bandwidth test."



Several web sites matches should appear.



Click on one of the sites that provides an online tool that can help you determine the
speed of your Internet connection performance.



Perform the test.



How fast is your connection?

Types of Internet Access

What Type of Access is Available to You?

Many ISPs offer different levels of Internet access. The next few pages detail some different
types of access.

56K Dial
-
up

Pros:



Uses existi
ng phone lines.



Lower cost
-
usually around $22.00 per month.

Cons:



Dial
-
up connection uses existing phone line, making it impossible to receive phone calls
unless another line is installed. Uses existing phone lines.



Slow
--

Can be limited to speeds of 28.8K to 33.6K. Upload speeds can be limited to as
low as 28.8, with download speeds approaching 56K under only perfect conditions.



Service can be somewhat unreliable (busy signals, spontaneously terminated sessions,
et
c).

ISDN (Integrated Services Digital Network)

Faster than 56K dial
-
up, but every ISP does not support ISDN.

Pros:



Can provide 2
-
4 times the speed of a 56K modem.



Uses digital rather than analog signals to transmit data.

Cons:



Requires special equipment

that can drive up your cost.



Data is not compressed so transmission rates can be comparable to 56k
-
at more cost.



May be replaced by other technologies.

DSL (Digital Subscriber Line)

Newer technologies such as DSL use an ISP to connect to the Internet a
nd allow faster
connections.

Pros:



Can fall back to slower speeds if the line cannot handle the modem's fastest speed.



Uses the existing phone line in most cases.



Does not tie up existing phone line, leading to "always on" access.



More bandwidth results
in improved streaming audio/video, online games, application
programs, telephone calling, video conferencing and other high
-
bandwidth services.



Can connect multiple computers on a single line.



Faster than a 56K dial
-
up modem.

Cons:



Availability
-
limited to

homes/businesses with a dedicated copper wire running between it
and the phone company's nearest central office.



Cost
-
includes installation fees and monthly charges (around $50.00 per month).



Need a firewall to ensure home network security. (additional co
st)



Service is not infallible.

Cable Modem

Cable modems, another newer technology that uses an ISP to connect to the Internet, allows
faster connections.

Pros:



Uses coaxial and/or fiber
-
optic cable rather than phone lines for data transmission, so
perfor
mance doesn't depend on your distance from a central cable office.



Can fall back to slower speeds if the line cannot handle the modem's fastest speed.



Convenient for homes already wired with cable access.



Does not tie up existing phone line, leading to
"always on" access.



More bandwidth results in improved streaming audio/video, online games, application
programs, telephone calling, video conferencing and other high
-
bandwidth services.



Can connect multiple computers on a single line.



Faster than a 56K di
al
-
up modem.

Cons:



Availability
-
limited to homes/businesses with cable access.



Cost
-
includes installation fees and monthly charges (around $40.00 per month).



Often requires commitment to a cable TV package.



A firewall is necessary to ensure home network
security (additional cost).



Service is not infallible.

Challenge!

Choose a level of Internet access that corresponds to your needs and budget. Do some
research on the Internet to determine the following:



What type of high
-
speed Internet access is availa
ble in your living area?

Web Browser Basics

Internet Explorer Browser


You have quite a number of choices of how to start up your browser.

Quick Launch:

The installation of IE4+ or WinXP

adds a new area to the Taskbar. This area
contains shortcuts to several programs, including Internet Explorer.


Desktop icon
: Somewhere on your Desktop there is an icon for IE by default.


Start menu:

Open the Start menu and then Programs. The icon for IE is probably in the area
below the folders and also in the folder named Internet Explorer.






Components of the Explorer browser window

Title Bar
-

bar on top of the window
that contains the name of
the
document

Menu Bar
-

a horizontal menu that
appears at top of the program window

Standard button toolbar
-

Icons for
single click access to most often used
menu commands

Address Bar
-

Contains the URL or
address of the active Web page

Document Window


Displays the
active Web page

Status Bar
-

Located at the bottom of the browser; shows the progress of the web page
transactions

Access Indicator


a small picture un the upper right corner of the browser.

Links Bar
-

A drop down menu containing a list of l
inked Web sites

Scroll bars
-

Vertical and horizontal scroll bars let you scroll vertically and horizontally if the
Web page is too long or too wide to fit within one screen.

Toolbars and Menu Bar


Back



Returns you to the previous page

Forward


Takes

you to the page you viewed before clicking the Back button

Stop


Stops the current page from loading

Refresh


Refreshes ore reloads the current Web page

Home


Takes you to your home page

Search



Connects you to the Microsoft Internet search sites

Favo
rites


Opens the favorite pane where you can store and access shortcuts to your most
frequently visited sites.

History


Opens the History pane, displays a record of all the sites you recently have visited.

Mail


Clicking the icon display a drop
-
down men
u with options to read your mail, create a new
messages, send a link, send a page, or read news.

Print


Prints the current document

Edit


Displays a drop
-
down menu with options to edit the Web page shown in the display area

Discuss


Initiates discussion
s with other online users

Create mobile Favorites


Used with a Pocket PC to save favorite links

Search Engines

Instead of trying to guess where certain information may be located on the Web,
search
engines

allow you to search both the Web and newsgroups.

A
search engine

searches for
keywords

and returns a list of documents where the keywords
can be found. Most search engines allow you to search using plain language relevant to the
topic of interest, meaning you don't have to know any special programming t
ricks to effectively
search the Web.

You're probably already familiar with search engines such as
Yahoo
,
Google
,
Excite
, or
AltaVista
. You may have even used a search engine to find our site.

Tips for Effective Searching

Beware of using slang or partial

words
. If you use slang or parts of words, you may
have some luck, but your results may be too broad. For example,
flick

instead of
movie
, or
Macs

instead of
Macintoshes

may yield different results.

Correct Spelling, Pluralization and Capitalization
.

Be aware of pluralizing your words,
and spell them correctly. For example,
good will
,
goodwill
,
Goodwill
,
Goodwills
, and
Good
Will
may yield different results.

AND
. Use AND (all caps) to search for multiple words that must appear in a web page. Some
sear
ch engines support a plus sign (+) in place of AND. For example,
free AND coupon
, or
free + coupon
.

NOT
. Use NOT (all caps) to exclude certain words or phrases. For example,
casserole NOT
chicken NOT beef
.

OR
. Use OR (all caps) to include any of the sea
rch words (rather than most.) For example,
George Washington OR Bush
.

Wildcards
. The percentage symbol (%) can be used to replace only one character. The
asterisk (*) can be used to replace multiple characters. For example,

post*

could produce
postwar
,
p
ostgame
, or
postmarital
.

Phrases
. Put quotes around a phrase so each word in the phrase isn't searched for
separately. For example, if you put quotes around
"free online computer training
,
"

the
search engine searches for that
entire phrase

in a web page.

However, if you simply type,

free online computer training
, the search engine searches for
each

of the words
individually in a web page.

Get Help
. Go to your search engine's
Help page

for more specific information on a
particular engine.

Try Something

New
. There are many different search engines on the Web. If you can't
find what you are looking for using your favorite engine, go somewhere else.


Bookmark it
. Add your favorite search engines to your Favorites to increase ease of
use. If you're not sure

how to do this, you'll learn how later in this unit.

Internet Explorer: Favorites

Access Favorites

When surfing the Web, you have probably found a number of sites you'd like to return to in the
future. You can keep track of your favorite

sites without having to remember long URLs using
the
Favorites

feature.

This feature comes with some pre
-
existing Favorites you may or may not find useful. You can
access, add to, find,

and
organize

your Favorites.

To access Favorites from the IE menu ba
r



Choose
Favorites

from the IE menu bar. (Ctrl + I)



A
Favorites

list appears. You may need to click the double arrow at the bottom of the
list to expand your choices.



Click a Favorite to go to that web page.

To access Favorites from the IE Explorer bar



Choose
View
Explorer bar
Favorites
or click the
Favorites

button on the
toolbar.



The
Explorer bar
opens and the
Favorites

list appears.



Click a
Favorite

to go to that web page.

To hide the Explorer bar's Favorites list



Click
the
Favorites

button
again

to
hide

the
Explorer bar
. (Ctrl + I)

OR



Click the

X

in the upper right of the
Explorer bar
.

Add to Favorites

To add to Favorites using the IE menu bar



Go to the page you want to add to your Favorites. For example:
http://www.gcflearnfree.org.



Choose
Fa
vorites

Add to Favorites

from the IE menu bar.



The
Add Favorite

dialog box opens.



The page title appears in the
Name

text box. For example: "Welcome to
GCFLearnFree.org Community Center." Change the page title if you wish. For example,
"GCF" may be
adequate.



Click
OK

to add it to your Favorites list.

To add to Favorites using the IE Explorer bar



Click the
Favorites

button on the toolbar.



The
Explorer bar

opens and the
Favorites

list appears.



Click the
Add

button.



The
Add Favorite

dialog box opens.



The page title appears in the
Name
text

box. Rename the page if you wish.



Your new
Favorite

appears in the

Favorites

list.

Organizing Favorites

Once you add several Favorites, you may want to
organize

them in folders. There are several
m
ethods of organizing your Favorites.

To Organize Favorites



Click the
Favorites

button.



The
Explorer bar
opens and the
Favorites

list displays.



Click a
Favorite

you want to organize.



Drag and drop

any Favorite into a pre
-
existing
folder
.

OR



Click the
Favorites
button (the

Explorer bar

opens) and click the
Organize

button.



The

Organize Favorites

dialog box opens. Use this dialog box to
Create a New
Folder, Rename, Move to Folder,

and
Delete
.



Drag and drop

Favorites into
folders
.

OR



Working in the
Organize Favorites

dialog box, click the

Move to Folder
button and
drag and drop Favorites

into
folders
.

Creating New Folders

You may need to

create new folders

in order to keep your Favorites organized.

To Create a New Folder



Click the
Favorites button
.

The
Explorer bar

opens and the
Favorites

list displays.



Click the
Add

button.



The
Add Favorite

dialog box opens.



Click the
New Folder

button.



The
Create New Folder

dialog box opens.



Name the folder

and click
OK
.



Click
OK again

to close the
Add
Favorite

dialog box and
add the new folder

to your
Favorites list.

OR



Click the
Favorites button

on the toolbar and click the
Organize

button.



The

Organize Favorites

dialog box opens.



Click the
Create Folder

button.



A
new folder

is created, ready to b
e
renamed
.

Renaming and Deleting Favorites

To Rename a Favorite



In the
Explorer bar's

Favorites

list,
right
-
click

a
Favorite
. Choose
rename

from
the shortcut menu.



The name is now
highlighted
, ready to be changed.



OR



Use the
Organize Favorites
dialog box.

OR

To Delete a Favorite



In the
Explorer bar's

Favorites

list,
right
-
click

a
Favorite
. Choose
delete

from the
shortcut menu.



A
confirmation message

appears. Choose
Yes
.

OR



Use the
Organize Favorites
dialog box.



History and Search

History

Using the
History

feature, you can find pages you've recently visited in the last few days.

To see a list of pages you've recently visited



Click the down arrow at the end of the

Address

bar.



To view, click any site from the list.

OR

To access your History
using the IE Explorer bar



Choose
View
Explorer bar
History

or click the
History

button on the toolbar.
(Ctrl + H)



The
Explorer bar

opens and the
History

list appears in the left side of the window.



Click a
week
or
day
.



Click a
folder
to display individual

pages.



Click the
web page icon

to display the web page.

To hide the Explorer's bar's History list



Click
the
History

button
again

to
hide

the
Explorer bar's

History list.

OR



Click the

X

in the upper right.

Customizing your History List

You can specify how

many pages are saved in your History list.

To specify how many pages are saved in the History list



Choose
Tools

Internet Options

from the IE menu bar.



Click the
General

tab



In the
History

area, change the number of days that the

History

list keeps trac
k of
your pages.



Click the
Clear History

button to clear your history and temporarily free up disk space
on your computer.

Search

You can also look for web pages using the
Search function
.

For ease of use, IE offers a couple of ways to search.

Searching
with the Explorer bar



Choose
View
Explorer bar
Search

click the
Search

button on the toolbar.



The
Explorer bar's Search function

displays. (Ctrl + E)



Choose a category for your search. (
Find a web page, Find a person's address,
Find a Business, Previous
Searches, or Find a Map radio buttons
)



Plug in any key words you think the page contained in the Find a web page containing
text box.



Click
Search
.



Results display in the bar. Click links that interest you.

OR



Click the
History

button. The
History
list

opens. Access the
Search function

by
clicking
Search

(located at the top of the
History
list).

To hide the Explorer's bar's Search function:



Click
the
Search

button
again.


OR



Click the

X

in the upper right of the
Search function
.

Search

You can also perform a web search by typing search terms
directly into the Address bar
.

Searching from the Address bar



Type in any key words you think the page may contain.



Click the
Go

button or press
Enter

on the keyboard.



MSN Search

results display in
a web page.



Choose a link that interests you.
s