Understanding Computers Chapter 8 The Internet and the World Wide Web.

Understanding Computers

Chapter 8

The Internet and the World Wide Web

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Learning Objectives• Discuss how the Internet evolved and what it is like

today.

• Identify the various types of individuals, companies, and organizations involved in the Internet community and explain their purposes.

• Describe device and connection options for connecting to the Internet, as well as some considerations to keep in mind when selecting an ISP.

• Understand how to effectively search for information on the Internet and how to properly cite Internet resources.

• List several useful things that can be done using the Internet, in addition to basic browsing and e-mail.

• Discuss censorship and privacy and how they are related to Internet use.

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Overview• This chapter covers:

– The evolution of the Internet

– The Internet community

– Different options for connecting to the Internet

– Internet searching

– Common Internet applications beyond Web browsing and e-mail

– Censorship and privacy issues

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Evolution of the Internet• Internet: Largest and most well-known computer

network, linking millions of computers all over the world

– Furnishes a standard way of sending messages and information across virtually any type of computer platform and transmission media

– While Internet has become a household word only during the past decade, it has actually operated in one form or another for much longer than that

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Evolution of the Internet• ARPANET: The predecessor of the Internet, named after

the Advanced Research Projects Agency (ARPA), which sponsored its development– Initially connected four supercomputers– Eventually grew into today’s Internet

• The World Wide Web: The collection of Web pages available through the Internet– Proposed by Tim Berners-Lee in 1989– Originally only text-based content– Release of the graphical Mosaic browser in 1993 led

to graphical content– Wide variety of content available via Web pages today

• Internet2: Researches advanced Internet applications and technologies

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Evolution of the Internet

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The Internet Community Today• Most members of the Internet community fall into one

or more of the following groups– Users: People who use the Internet– Internet service providers (ISPs): Provide access to

the Internet, typically for a fee

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The Internet Community Today– Internet content providers: Supply the information

that is available on the Internet• Businesses and schools• Government• Individuals

– Application service providers (ASPs): Provide access to Web-based software applications

– Web services: Added to Web pages to provide specific services for end users

– Infrastructure companies: Own or operating the physical structure of the Internet

– Hardware and software companies

– The government and other organizations

• Internet Society, ICANN, W3C, etc.

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Myths About the Internet• Myth 1: The Internet is free

– Most people and businesses pay for Internet access

– Free services are often in exchange for providing contact information or viewing advertisements

– Fee-based content is growing

– Micropayments may be implemented in the future for Web content

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Myths About the Internet• Myth 2: Someone controls the Internet

– No single entity controls the Internet

– Governments can somewhat regulate Internet use within its country but difficult to control it well

• Myth 3: The Internet and World Wide Web are identical

– Internet = physical network

– WWW = one resource (Web pages) available via the Internet

– Other resources are available via the Internet

• e.g. FTP

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FTP

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Getting Set Up to Use the Internet• Typically involves three decisions:

– Determining the type of device you will use to access the Internet

– Selecting the type of connection desired

– Deciding on the Internet service provider to be used

• Once these determinations have been made, your computer can be set up to access the Internet

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Type of Device• Possible devices include:

– Desktop, notebook, or tablet PCs

– Internet appliances

– Mobile devices

– Gaming devices

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Type of Connection and Internet Access

• Connections can be:– Dial-up

• PC has to dial via a phone line to connect• Conventional dial-up

– Slower, but cheaper– Ties up phone lines– Relatively secure from hackers

• ISDN– Faster, but pricey– Doesn’t tie up phone line– Used by businesses and individuals

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Type of Connection and Internet Access

– Direct (always on)

• PC is continually connected to the Internet

• Direct connections are typically broadband

• Used in the home and office

• Because you are always connected, it is important to protect your computer from hackers

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Direct Connections• T1 lines: High-speed, usually used by schools and

large businesses– T3 lines are even faster

• Cable: Most widely used home broadband connection• DSL: Broadband delivered over telephone lines

– Must be less than 3 miles from a switching station– Transmits over telephone lines but does not tie up

the line• Satellite: Broadband option for rural areas

– Slower and more expensive that cable or DSL– Available in many areas other broadband options

are not

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Direct Connections• Fixed wireless: Uses radio transmission towers rather

than satellites– Not available in all areas– Expected to use WiMAX• Broadband over Fiber (BoF): Delivers over fiber-optic

cabling all the way to the building– Available in limited areas– Fast but expensive• Mobile wireless: Access via mobile phone or device• Hotspot: Public wireless networks– Both free and fee-based are available– Currently Wi-Fi so short range, but WiMAX may soon

be an option

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Hotspots

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Common Types of Internet Connections

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Selecting an ISP

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Setting Up Your PC• To set up your PC

– Install necessary hardware

– Install necessary software

– Select user name, access telephone number (for dial-up connections), and a payment method

– Perform any necessary set-up to share the connection with other computers or devices

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Searching the Internet• Effective Internet searching: A very important skill• Search sites: Web sites that help you find Web pages

containing the information you are seeking• Typically use a search engine in conjunction

with a database containing information about Web pages to locate appropriate Web pages

• Many search sites available• Real-time search engines are emerging

– Search the Web live rather than relying on a database

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Searching the Internet• Keyword search

– Keywords are typed in a search box to locate information on the Internet

– Matching Web pages are called hits– Clicking on a Web page name displays that page

• Directory search– Categories are selected to locate information on

the Internet• Some search sites search multiple search sites

(metasearch sites) and others allow natural language searches

• Many search sites contain additional tools– Search for music files, image files, newsgroups,

news articles, maps, people, telephone numbers– Google is one of the most versatile search sites

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Searching the Internet

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Search Site Tools

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Search Strategies• Use phrase searching (more than one keyword)

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Search Strategies• Use Boolean operators (AND, OR, NOT)

• Use multiple search sites

• Use appropriate keywords

• Use synonyms (different words that mean the same thing)

• Use variant word forms (variations of your keywords, alternate spellings, etc.)

• Use wildcards (such as * to search for keyword patterns)

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Search Strategies• Use field searches (searches limited to a particular

characteristic, such as page title, page text, URL, or domain)

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Evaluating Search Results• The quality of a hit can be preliminarily evaluated by

looking at:– Page title and description– Company or organization hosting the page

• General guidelines for evaluating a Web page include considering:– Source– Author– Timeliness– Accuracy

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Evaluating Search Results

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Citing Internet Resources• To avoid plagiarism, proper citation procedures should

be used for all Internet content used in a paper, book, or on a Web site

• Plagiarism is discussed in more detail in Chapter 16

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Beyond Browsing and E-Mail• Many other activities available via the Internet in

addition to Web browsing and e-mail– Online communications– Social networking– Online shopping and investing– Online entertainment– Online news, reference, and information– Online education and writing

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Types of Online Communications• Types of online communications

– Instant messaging (IM): Exchange of real-time messages

• Buddy list• Presence technology

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Types of Online Communications– Voice over Internet

Protocol (VoIP): Making telephone calls over the Internet

• PC to PC• Voice over Wi-Fi• Permanent set-

ups

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Types of Online Communications– Discussion groups (message boards, newsgroups,

or online forums): Read and post messages– Chat rooms: Multiple users chat in real time– Videoconferencing: Two-way conference using

computers and communications technology– Webinars: Web seminar, more one-way– Blogs (Web log): Post short, frequently updates

entries in chronological order

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Social Networking• Social networking sites: Create a community of

individuals with common interests

– MySpace, Facebook, etc. allow people to post information about themselves

– Video and photo sharing (YouTube, Flickr, etc.

– Collaborative news communities (Digg)

– Social bookmarking (del.icio.us)

– Used for politics and business

• Business networking sites

• Family networking sites

• Users should be careful not to reveal too much about themselves for safety reasons

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Social Networking

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Online Shopping and Investing• E-commerce: Online financial transactions

• Precautions

– Be sure all e-commerce activities are performed via a secure Web server (https://)

– Use a credit card whenever possible

• Online shopping: Purchasing goods and services online

– Can purchase items via manufacturers, large businesses, small businesses, etc.

– Usually paid via credit card, though other options may be available

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Online Shopping and Investing• Online auctions: Buying via an auction format online

(eBay, etc.)

– Buy from individuals

– Can bid until auction closes

– Buyer arranges payments and delivery with seller

– Seller pays auction fees

• Online banking (transfer funds, check balances, pay bills, etc.)

• Online investing (buy and sell stocks, bonds, and other securities

– Online portfolios

– Some stock quotes are delayed

• Auction and stock quote pages may need to be reloaded to show current data

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Online Shopping and Investing

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Online Entertainment• Online music

– Internet radio stations: Listen to music live– Online music stores: Used to purchase and

download music singles and albums in digital format legally

– Some available legally via peer-to-peer (P2P) file sharing services

• Online TV, online videos, video-on-demand (VoD)– Live TV, full episodes– Music, news, home videos, etc.– VoD: Movies and other video content ordered and

delivered on demand• Online gaming: Games played over the Internet

– Web-based games, online multiplayer games, etc.

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Online Entertainment

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Online News, Reference, and Information

• Online news– Available through Web sites belonging to news

organizations, television networks, newspapers, magazines, etc.

– News sites are usually regularly updated throughout the day

– News archives are often available (sometimes requires a fee)

• Reference sites– Provide access to specific types of useful

information– Phone and address directories, weather, maps,

home values, encyclopedias, dictionaries, etc.

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Online News, Reference, and Information

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Portal Pages, RSS Feeds, Podcasts, and Widgets

• Portal Web page: Designed to be displayed as a browser’s home page and visited on a regular basis– Often contain

news, calendars, e-mail, and other tools

– Usually personalized

– iGoogle, My Yahoo!, My MSN, etc.

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Portal Pages, RSS Feeds, Podcasts, and Widgets

• RSS (Really Simple Syndication): Delivers news, podcasts, and other regularly published content– Individuals subscribe to an RSS feed and new

content is delivered to them as it becomes available

• Podcasts: Recorded audio or video available via the Internet– Prepared by individuals and companies

• Widgets: Small programs displayed on portal pages, desktops, dashboards, etc.– Can be used to display headlines, among other

uses– e.g. Windows Vista gadgets

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Product, Corporate, and Government Information

• The Web is a useful tool for locating product and corporate information, as well as governmental information and publications

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Online Education• Online education: Using the Internet to facilitate

learning

– Web-based training (WBT): Instruction delivered via the Web

• Corporate training, tutorials, etc.

– Distance learning: Students take classes from location other than campus

• Advantages: Self-paced instruction, flexible location, up-to-date material, immediate feedback, and customized content

• Disadvantages: Technology requirements and problems, anonymity, and lack of face-to-face contact

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Online Education• This textbook has:

– Web site at www.course.com/uc12 with interactive activities, practice tests, etc.

– Blackboard learning platform

– SAM 2007 testing, etc.

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Online Education– Online testing: Taking tests via the Internet

• Available for both objective and performance-based exams

• Typically are graded automatically

• Security is an issue

– Authorizedtesting centers

– Securetesting systems

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Online Education– Online writing

• Blogs: Personal Web logs

• Wikis: Editable collaborative Web page

• E-portfolios: Personal online portfolio

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Censorship and Privacy Issues• Censorship issues

– Some countries block some Internet content

– Free speech vs. offensive or indecent materials

– Internet filtering: Using software or browser options to block access to particular Web pages or types of Web pages

• Used by individuals, schools, employers, public computers, etc.

• Can use browser settings or special filtering software

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Internet Filtering

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Censorship and Privacy Issues• Web browsing privacy: Privacy of Web activities

– Cookies: Small files stored on the user’s hard drive by a Web server

• Add functionality (such as shopping carts and personal preferences) to Web sites

• Can be used to track Web activity

• Cookie information can be personally identifiable or non-personally identifiable

• Cookie data can be viewed or deleted

• Cookie settings can be changed and software can be used to manage cookies

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Cookies

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Cookies

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Censorship and Privacy Issues• Web bugs: Small, usually invisible, images on a Web

page that transmits data to a Web server– Difficult to spot or stop– Software can be used to notify you when Web bugs

are being used• Spyware: Software that transmits data secretly

through the user’s Internet connection– Can be blocked and/or removed using security

software (discussed in Chapter 9)• Adware: Software supported by onscreen advertising

– Often included in free programs

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Censorship and Privacy Issues• E-mail privacy: Privacy of the e-mail messages you

send and receive– Only encrypted e-mail can

be transmitted privately– Employers and ISPs have

access to the e-mail you send through those organizations

– Businesses and ISPs typically archive e-mail messages

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Summary• Evolution of the Internet

• Getting Set Up to Use the Internet

• Searching the Internet

• Beyond Browsing and E-Mail

• Censorship and Privacy Issues