1. The Internet & the World Wide Web
Chapter 2
Exploring Cyberspace

2. Chapter 2: Key Questions
2.1 What are the means of connecting to the Internet, and how fast are they?
2.2 What are the three types of Internet service provider, and what kinds of service do they provide?
2.3 What are the components of an address, and what are netiquette and spam?
2.4 What are Web sites, Web pages, browsers, URLs, and search engines?
2.5 What are FTP, Telnet, newsgroups, real-time chat, and e-commerce?

3. To Access the Internet, You Need…
An access device
A physical connection
An Internet Service Provider (ISP)
Can you give examples of each?

4. Physical Connection Telephone (dial-up) modem
Several high-speed phone lines
ISDN
DSL T1
Cable modem
Wireless

5. Data Transmission Speeds
Upload – data from local computer to remote
Download – data from remote to local
Bandwidth
Data that is sent through a communications channel in a given amount of time
Data transmission speeds:
Bps – bits per second
Kbps – kilobits per second
Mbps – megabits per second
Gbps – gigabits per second
8 bits = 1 byte = 1 character

6. Telephone Modem
See panel 2.3 on page 39

7. High Speed Phone Lines ISDN (Integrated Services Digital Network)
Hardware & software
Uses traditional telephone lines (128 Kbps)
DSL (digital subscriber line)
Always on
Transmission rate is consistent ( Mbps)
Must live within 3.3 miles of a phone company switching office
T1 line (1.5 Mbps)
Used by corporate, government, and academic sites

8. Cable Modems
Connects a PC to a cable-TV system that offers Internet access
Always on
Competes with DSL
Transmission rate may not be consistent during peak hours
Speed:10 Mbps

9. Wireless Systems Communications satellite Other wireless connections
Radio waves (microwaves) transmitted from earth-based stations
Receives data at 400 Kbps & sends data at 56 Kbps (with phone line)
Other wireless connections
Radio waves for cellular phones
Sends data up to 155 Mbps

10. Three Types of ISP Services
Free-service providers
NetZero, AltaVista, BlueLight.com
Advertisements and personal info
Basic-service providers
Offer local connection
Full-service providers
AOL, Earthlink, MSN
More technical support and international access

11. How to Get E-mail Software?
Purchase
MS Outlook express, Lotus Notes
Get as a part of other package
Netscape Communicator
Provided by your ISP
AOL
Free Services
Yahoo, Hotmail

12. Joe_Black@earthlink.net.us E-mail Addresses User ID Domain Name
Domain Abbreviations:
.com Commercial businesses
.edu Educational and research institutions
.gov U.S. government agencies and bureaus
.int International organizations
.mil U.S. military organizations
.net Internet network resources
.org Nonprofit and professional organizations
Domain Top-level domain Country
(location) (domain type)

13. E-mail Attachments Instant messaging Attached to emails
Formatting preserved
Recipient must have software to read them
Instant messaging
Cross between and phone
Message pops up instantly on the screen if user is logged on

14. Netiquette Use FAQs Avoid flaming Don’t shout Avoid sloppiness
Make attachments small
Quote only relevant portion when replying
Avoid spams

15. World Wide Web Uses of the WWW Why the WWW is inviting & easy to use
Entertainment
E-commerce
E-tailing, auction, online finance, on-line job hunting, B2B
Why the WWW is inviting & easy to use
Multimedia format : graphics, video, audio, text
Use of hypertext

16. Web Terms Web site Web pages Browsers
a computer with a domain name is called a site
Web pages
a document that can include text, pictures, sound, and video
Browsers
software that enables users to view Web pages URLs
URLs (Universal Resource Locator)
a string of characters that point to a specific Web page
Web portals
Web sites that group together popular features

17. Web Terms Multimedia format HTML (hypertext markup language) HTTP
graphics, video, audio, text
HTML (hypertext markup language)
A language used to specify document structure, formatting, and links to other documents
HTTP
hypertext transfer protocol –rules that allow browsers to connect with Web servers

18. Search Engine Types Human-organized search sites
subject experts (humans) do the indexing
Yahoo!. AOL, MSN, Netscape, Lycos
Computer-created search sites
software "spiders" (software) do the indexing
Northern Light, Excite, WebCrawler, FAST Search, Inktomi
Hybrid search sties
humans supplemented by computer indexes
AskJeeves, Direct Hit, Go, GoTo.com, Google, HotBot, Snap
Metasearch sites
sends query to other search tools and compile the results
Go2Net/MetaCrawler, SavvySearch, Dogpile, Inference

19. Multimedia on the Web Plug-ins & helper applications
Multimedia development
Applets, Java, JavaScript, ActiveX
Text and images
Animation
Video
Audio
Plug-ins – also called a player or a viewer - is a program that adds a specific feature to a browser, allowing it to play or view certain files
Helper applications – or add ons; runs multimedia elements separate from the browser
Multimedia development
Applets – small programs that can be quickly downloaded and run by most browsers
Java – complex programming language that enables programmers to create animated and interactive web pages
JavaScript & ActiveX – may be used to create activities such as scrolling banners and pop-up menus
Animation – the rapid sequencing of still images to create the appearance of motion
Streaming video - the process of transferring data in a continuous flow so that you can begin viewing a file even before the end of the file is sent
Streaming audio – allows you to listen to a file while the data is still being downloaded

20. More Internet Resources
FTP – File Transfer Protocol
a program that can transfer files to one compute to another
Telnet
a program that allows you to connect to remote computers on the Internet
Newsgroups
a giant electronic bulletin board on which users conduct written discussions about a specific subject
Real-time chat
participants have a typed discussion while online at the same time