Computer Concepts Illustrated

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Nov 5, 2013 (4 years and 5 days ago)

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Computer Concepts


Illustrated
8
th

edition

Unit G: The Web and E
-
Commerce

Computer Concepts


Illustrated 8th Edition

2

Objectives

Introduce Web technology

Explore Web browsers

Examine Other Web and Internet services

Examine Web page features

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Objectives (continued)

Use search engines

Introduce e
-
commerce

Secure e
-
commerce transactions

Enhance Web technology

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Introducing Web Technology

Internet: a communications network that
transmits data

Web
:

a collection of documents called Web
pages that are accessed over the Internet
and are related by using links

Web page
:

a document that can contain
text, graphics, video, and audio


A Web page is an
HTML document

Web site
:

a collection of related Web pages

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Introducing Web Technology
(continued)

Browser
(or a
Web browser
): software that
displays Web page elements

Link
(or
hyperlink
):

a navigation tool on a
Web page


Hypertext

URL
(Uniform Resource Locator): the
address for a Web page

Web resource
:

any data file that has a URL


HTML document, graphic, video, sound file,
etc.

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Figure G
-
2: How Web pages get to your computer

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Introducing Web Technology
(continued)

Web server
:

a computer that uses special
software to transmit Web pages over the
Internet

HTTP (Hypertext Transfer Protocol)
:

the
communications protocol used to transport
data over the Web

HTTP status code
:

indicates whether or
not the browser’s request can be fulfilled


“404 Not Found” message

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Exploring Web Browsers

Popular browsers:


Microsoft Windows Internet Explorer (IE)


Mozilla Firefox


Google Chrome


Apple Safari (for the Mac)

Tabs: a way to view more than one Web
page within one browser window

Favorite
(or
bookmark
): a saved link to a
Web site

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Figure G
-
3: Popular browsers

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Exploring Web Browsers (continued)

Helper application


Also called
add
-
on
,
plug
-
in
, or
player



Extends a browser’s ability

Installing browser updates is important

Web pages can be viewed on PDAs,
smartphones, and other portable computing
devices

Web cache
:

stores temporary Web files

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Examining Other Web and Internet
Services

FTP (file transfer protocol)
:

provides a
way to transfer files from one computer to
another over any TCP/IP network

Podcast
(or Webcast): an audio file
distributed through downloads or a feed

RSS
:

a format for feeding or syndicating
content from Web sites to user’s computer

Social networking
:

use of the Web to stay
connected with family, friends, colleagues


Facebook, LinkedIn, MySpace, Bebo

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Examining Other Web and Internet
Services (continued)

Blog
:

a Web site where people can provide
commentary or news on a particular subject


Can also use as personal online diaries

Wiki
:

a collaborative Web site that can be
accessed and edited by anyone


Wikipedia

Communicating in real time:

instant
messaging (IM)
, Voice over IP

Web 2.0
refers to new and innovative ways
of using the Web

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Figure G
-
8: Wikipedia

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Examining Web Page Features

HTML (Hypertext Markup Language)


A set of specifications for creating HTML
documents that a browser can display as a
Web page


HTML is a
markup language


HTML tags
specify how the document
should appear when displayed


XHTML
is the version after HTML 4

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Figure G
-
10: A source HTML document and its Web page

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Examining Web Page Features
(continued)

Mailto: link


Automatically opens a preaddressed email
form

HTML tags are used to create links to other
Web documents

Web page authoring tools


Text editors, such as Notepad


HTML conversion utility


Web authoring software



Online Web page authoring tools

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Using Search Engines

Web search engine
(or
search engine
)


A program designed to help people locate
information on the Web


Contains four components:


Web crawler
: combs the Web to gather data
that is representative of the Web pages


Indexer
: makes pages easy to find based on
their contents


Database


Query processor
: looks for search terms in
the database and displays a list of relevant
Web sites in browser

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Figure G
-
12: Search results

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Using Search Engines (continued)

Order of Web sites in search results


Depends on relevancy criteria, such as:


Key word matches


Link popularity


Keyword stuffing
:

an unethical practice in
which
meta keywords

are manipulated to
gain high relevancy rankings

Boolean operator
(or a search operator): a
word or symbol that describes a relationship
between keywords


AND, OR, NOT

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Introducing E
-
Commerce

E
-
commerce
:

financial transactions
conducted over a computer network


B2C (business
-
to
-
consumer) e
-
commerce


C2C (consumer
-
to
-
consumer) e
-
commerce


B2B (business
-
to
-
business) e
-
commerce


B2G (business
-
to
-
government) e
-
commerce

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Figure G
-
15: E
-
commerce shopping

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Introducing E
-
Commerce (continued)

Online shopping cart
(or
online shopping
bag
): cyberspace version of a shopping cart


Most shopping carts work by using cookies


Cookie
:

data generated by a Web server and
stored in a text file on user’s computer


Users can choose to allow cookies or not

Advertising on Web sites


Banner ad


Pop
-
up ad


Banner and pop
-
up ads earn revenue based
on
click
-
through rate

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Securing E
-
Commerce Transactions

Password security used to prevent
unauthorized access

A
secure connection
encrypts the data
transmitted between a computer and a site

Technologies that create secure
connections include:


SSL (Secure Sockets Layer)


TLS (Transport Layer Security)


S
-
HTTP (secure HTTP)

Encryption
:

science of coding data

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Figure G
-
18: Identifying a secure connection

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Securing E
-
Commerce Transactions
(continued)

Ways to pay for online purchases:


Submitting credit card number directly


Using a third
-
party payment service, such
as PayPal


Person
-
to
-
person payment


Electronic wallets


One
-
time
-
use credit card numbers

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Enhancing Web Technology

HTML script
: a series of program
instructions


Allow Web pages to be interactive

HTML form
: used to collect user input for
different types of Web sites

Scripts can run on a client or a server


Server
-
side script
:

scripting statements
that run on a server


Client
-
side script
:

scripting statements that
run on user’s local computer

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Figure G
-
20: HTML form

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Enhancing Web Technology
(continued)

Java applet
:

an application written in the
Java programming language


Java applets are fairly safe

ActiveX control
:

a compiled program that
can be referenced from within an HTML
document, downloaded, installed, and
executed


ActiveX controls include
digital certificates

to increase their security

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Talking Points: Regulating the Web

Internet hosts a significant amount of
provocative and disturbing material


“Netizens”: members of the online
community of the Internet


Censorship advocates


Free
-
speech supporters


Cybercensorship


In many countries, free speech is not a
basic right conferred to all citizens


“Great Firewall of China”

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Summary

This chapter introduced:


Technologies that bring the Web to user’s
computer screen


Tools that user’s use to view and navigate
Web pages


E
-
commerce


Technologies that enhance user’s Web
experience


Issues regarding censorship on the Web