fundamentals of internet and world wide web

FUNDAMENTALS OF INTERNET AND WORLD WIDE WEB

Discovering Computers 2012: Chapter 21

The Internet

• The Internet is a worldwide collection of networks that links millions of businesses, government agencies, educational institutions, and individuals

Discovering Computers 2012: Chapter 2 2Page 74 Figure 2-1

Evolution of the Internet

• The Internet was first developed by the Advanced Research Projects Agency (ARPA) and the U.S. Department of Defense(DoD) for scientific and military communications and to avoid the loss of communication in the event of any single installation being inaccessible due to war or natural disasters.

3Discovering Computers 2012: Chapter 2

ARPANET

• Project started by the U.S. Department of Defense (DoD) in 1969– Ancestor of the Internet– The ARPANET (Advanced Research Projects Agency

Network) developed by ARPA of the United States Department of Defense during the Cold War, and it was the beginning of the global Internet.

– Initially connected four supercomputers– Eventually grew into today’s Internet

• In 1990, ARPANET ceased to exist. • 1990 – first search-engine (Archie)

4Discovering Computers 2012: Chapter 2


• The Internet originated as ARPANET in September 1969 and had two main goals:

Discovering Computers 2012: Chapter 2 5Page 75

Allow scientists at different physical locations to share

information and work together

Function even if part of the network were

disabled or destroyed by a disaster


1969ARPANET becomes functional

1984ARPANET has

more than 1,000

individual computers linked as

hosts

1986 NSF connects NSFnet to

ARPANET and becomes

known as the Internet

1995 NSFNetterminates its network

on the Internet and

resumes status as research network

1996Internet2 is

founded

Today More than 550

million hosts connect to

the Internet

Discovering Computers 2012: Chapter 2 6Pages 75 - 76

7

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

8

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– www & internet is two separate concepts. Web or WWW is the

fastest growing part of the internet. Its most important feature is “website”.

– Internet is the network of many networks. It is a global network linking tens of thousands of networks & millions of individual users, businesses, schools & Government agencies.

•


• Each organization is responsible only for maintaining its own network– The World Wide Web Consortium (W3C) oversees

research and sets guidelines and standards

• Internet2 connects more than 200 universities and 115 companies via a high-speed private network


Type of Connection and Internet Access

• Many home and small business users connect to the Internet via high-speed broadband Internet service


Cable Internet service

DSL Dial Up Fixed wireless

Cellular Radio

NetworkWi-Fi

Satellite Internet Service

Type of Connection and Internet Access

• Dial up Connection• ISDN• DSL• Cable• Wireless Internet Connection• Satellite

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Dial Up Connection (Analog)

Using a modem connected to your PC

• PC has to dial a number provided by ISP via a phone line to connect– Slower, but cheaper– Ties up phone lines– Quality is not good

• Dial-up is an analog connection because data is sent over an analog, public telephone network. The modem converts received analog data to digital and vise versa.

• Typical Dial-up connection speeds range from 2400 bps to 56 Kbps.

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ISDN

• Integrated services digital network (ISDN) is an international communications standard for sending voice, video, data and fax transmissions over the same phone line

• Typical ISDN speeds range from 64 Kbps to 128 Kbps.• Faster then dial up , but pricey• Doesn’t tie up phone line• Used by businesses and individuals• Dial before use

13

What is Broadband?

• Broadband Internet access, often shortened to just "broadband", is a high data rate connection to the internet

14

Cable• Cable connections are considered one of the best types

of internet connection available to the home user, they offer very fast and reliable connections with a fixed monthly fee.

• The broadband cable connection is provided by the local cable TV provider.

• Because the coaxial cable used by cable TV provides much greater bandwidth than telephone lines, a cable modem can be used to achieve extremely fast access. Cable speeds range from 512 Kbps to 20 Mbps.

• Because cable connections are Always on you will need a firewall and antivirus to protect your PC

15

DSL

• DSL (Digital subscriber line)is also called an always on connection • DSL is provided by the telephone company over your existing

copper wire. With DSL, you can get both voice and data over the same pair of wires.

• DSL service is a technology for bringing high-bandwidth broadband internet service to homes and small businesses over ordinary copper telephone lines

• There is no need to dial-in to your ISP as DSL is always on. • With DSL service all you need to do is plug your PC into your DSL

modem and then from your modem to your normal telephone jack• DSL Speed - 28Kbps – 1.5Mbps

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Satellite

• The slowest broadband service is provided by satellite.

• Although this is a good replacement for dial-up for those people living in remote rural areas, the installation costs are quite high, but the ongoing monthly charges are competitive to both cable and DSL.

• Slower and more expensive that cable or DSL

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Wireless Connection

• Fixed wireless: Wireless Internet, or wireless broadband is one of the newest Internet connection types, uses radio frequency bands and towers for internet connection.

• Wireless Internet provides an always-on connection which can be accessed from anywhere — as long as you geographically within a network coverage area.

• Hotspot: Public wireless networks– Both free and fee-based are available– Currently Wi-Fi so short range, but WiMAX may soon be an

option18

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Direct Connections• Fixed wireless: Uses radio transmission towers rather than

satellites– Not available in all areas

• 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

21

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


• An access provider is a business that provides individuals and organizations access to the Internet free or for a fee



ISP (Internetservice provider)

Regional ISPs provide Internet

access to a specific geographical area

National ISPs provide Internet

access in cities and towns nationwide

Online service provider (OSP)

Has many members-only features

Popular OSPs include AOL (America

Online) and MSN (Microsoft Network)

Wireless Internet service provider

Provides wireless Internet access to

computers and mobile devices

May require a wireless modem


The World Wide Web

• The World Wide Web, or Web, consists of a worldwide collection of electronic documents (Web pages)

• Can contain text, graphics, sound, video, and built-in connections

• A Web site is a collection of related Web pages and associated items

• A Web server is a computer that delivers requested Web pages to your computer

• Web 2.0 refers to Web sites that provide a means for users to interact

• Hypertext Markup Language (HTML): standard page description language for Web pages


The World Wide Web

• A Web browser, or browser, allows users to access Web pages and Web 2.0 programs


Internet Explorer Firefox Opera

Safari Google Chrome

The World Wide Web


The World Wide Web

• A home page is the first page that a Web site displays

• Web pages provide links to other related Web pages– Surfing the Web

Discovering Computers 2012: Chapter 2 29Pages 82 - 83 Figure 2-7

• Some Web pages are designed specifically for microbrowsers

The World Wide Web

• A Web page has a unique address called a URL or Web address

Discovering Computers 2012: Chapter 2 30Pages 82 – 83 Figure 2-8

The World Wide Web

• An IP address is a number that uniquely identifies each computer or device connected to the Internet

• A domain name is the text version of an IP address– Top-level domain (TLD)

• A DNS server translates the domain name into its associated IP address


The World Wide WebWhat is downloading? The process of a computer receiving information Depending upon connection speed, downloading can take

from a few seconds to several minutes

Uploading: is the process of transferring a file from local computer to remote computer over network.

The World Wide Web

• Tabbed browsing allows you to open and view multiple Web pages in a single Web browser window


The World Wide Web

• Two types of search tools are search engines and subject directories (http://dir.yahoo.com/)


Search engine

Finds information related to a

specific topic

Subject directory

Classifies Web pages in an

organized set of categories

The World Wide Web


The World Wide Web

• A search engine is helpful in locating items such as:


Images Videos Audio Publications

Maps People or Businesses Blogs

The World Wide Web


The World Wide Web

• Some Web browsers contain an Instant Search box to eliminate the steps of displaying the search engine’s Web page prior to entering the search text


The World Wide Web

• Search operators can help to refine your search


The World Wide Web

• There are thirteen types of Web sites


Portal News Informational Business/Marketing

Blog Wiki Online Social Network

Educational

The World Wide Web

Entertainment Advocacy Web Application

Content Aggregator

Personal


Video: Tell Your Stories via Vlog

Discovering Computers 2012: Chapter 2 42

CLICK TO START

The World Wide Web

• Information presented on the Web must be evaluated for accuracy

• No one oversees the content of Web pages


The World Wide Web

• Multimedia refers to any application that combines text with:


The World Wide Web

• A graphic is a digital representation of nontext information

• Graphic formats include BMP, GIF, JPEG, PNG, and TIFF


The World Wide Web

• A thumbnail is a small version of a larger graphic


The World Wide Web

• Animation is the appearance of motion created by displaying a series of still images in sequence


The World Wide Web

• Audio includes music, speech, or any other sound– Compressed to reduce file size

• You listen to audio on your computer using a player• Streaming is the process of transferring data in a

continuous and even flow


The World Wide Web


The World Wide Web

• Video consists of images displayed in motion


The World Wide Web

• Virtual reality (VR) is the use of computers to simulate a real or imagined environment that appears as a three-dimensional space


The World Wide Web

• A plug-in is a program that extends the capability of a Web browser


The World Wide Web

• Web publishing is the development and maintenance of Web pages


Plan a Web site

Analyze and

design a Web site

Create a Web site

Deploy a Web site

Maintain a Web

site

E-Commerce

• E-commerce is a business transaction that occurs over an electronic network– M-commerce identifies e-commerce that takes place

using mobile devices


E-Commerce


E-commerce

Business-to-

consumer (B2C)

Consumer-to-

consumer (C2C)

Business-to-

business (B2B)

E-Commerce


Other Internet Services

• E-mail is the transmission of messages and files via a computer network

• An e-mail programallows you to create, send, receive, forward, store, print, and delete e-mail messages



• A mailing list is a group of e-mail names and addresses given a single name– Subscribing adds your e-mail name and address– Unsubscribing removes your name



• Instant messaging (IM) is a real-time Internet communications service



• A chat is a real-time typed conversation that takes place on a computer

• A chat room is a location on an Internet server that permits users to chat with each other



• VoIP (Voice over IP) enables users to speak to other users over the Internet– Also called Internet

telephony



• A newsgroup is an online area in which users have written discussions about a particular subject– Typically requires a

newsreader

• A message board is a Web-based type of discussion group



• FTP (File Transfer Protocol) is an Internet standard that permits file uploading and downloading with other computers on the Internet

• Many operating systems include FTP capabilities• An FTP server is a computer that allows users to

upload and/or download files using FTP


Netiquette

• Netiquette is the code of acceptable Internet behavior


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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

67

Types of Online Communications• Types of online communications

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

• Buddy list

68

Types of Online Communications– Voice over

Internet Protocol (VoIP): Making telephone calls over the Internet

• PC to PC• skype

69

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

72

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

75

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

77

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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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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Online News, Reference, and Information

80

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– iTunes Store puts thousands of free podcasts at your

fingertips• 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.

84

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