Transcript Computer Concepts – Illustrated 8th edition

Computer Concepts – Illustrated
8th edition
Unit G: The Web and E-Commerce
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) ecommerce
 C2C (consumer-to-consumer) ecommerce
 B2B (business-to-business) e-commerce
 B2G (business-to-government) ecommerce
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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
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