the internet and the world wide web. univ. of california at santa barbara univ. of california at los...
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THE INTERNET AND
THE WORLD WIDE WEB
Univ. of California at Santa Barbara
Univ. of California at Los Angeles
Univ. of Utah
Stanford Research Institute
ARPANET—Predecessor to the Internet
1969—4 computers
The World Wide Web
Way of accessing information over the Internet
Began in 1989
Tim Berners-Lee
Characterized by Hyperlinks
The Internet
Massive ‘network of networks’ connecting computersBegan in 1969
How the World Wide Web Works: Berners-Lee developed the three technical keystones of the
Web: (1) the language for encoding documents (HTML,
Hypertext Markup Language);
(2) the system for linking documents (HTTP, Hypertext Transfer Protocol); and the
(3) www.whatever system for addressing documents (URL, Uniform Resource Locator).
HYPERTEXT MARKUP LANGUAGE (HTML)
HTML--primary coding system for Web pages.
Hyperlinks are buttons, highlighted or underlined text that send the user to a related document.
A protocol--set of rules and procedures for exchanging information among computers on a network.
HTTP: HYPERTEXT TRANSFER PROTOCOL
Hyperlink—method of navigating between sites.
URL (UNIFORM RESOURCE LOCATOR).
URL--address of an Internet file.
Usually 4 parts--protocol, server, path and filename.
http://www.microsoft.com/windows/default.asp
protocol server path filename
What are domains?
•Divide the WWW into categories based on the nature of their owner and form part of a site’s address, or URL.
•Common domain names are:
.com commercial enterprises
.org non-profit organizations
.net for networks
.edu for educational organizations
.gov for government organizations
.mil for military services
Based on this, could you guess some URLs?
INTERNET SERVICE PROVIDERS
*Dial-Up—Phone Line
*BroadbandCable—TV CableDSL—Phone LineSatellite—Satellite DishWireless—Radio Waves
Considerations:
Cost Speed Reliability Extras provided Tech. Support Other costs & fees
Dial-Up
Cable DSLSatelli
teWirele
ss$7-$15 $40-$50 $35-$50 Up to $100 $25-$50
People PCNet Zero
CoxTime Warner
VerizonAT&T
Hughes Net
SkywayusaEagleCom
56 kbps512kb-20
mbps125kb-8
mbpsup to 6 mbps
up to 30 mbps
Affected by number of
users
Affected by distance from hub
Affected by
weather
Installation charge?
Installation charge?
Cost of satellite?
Installation?
Installation charge?
WHAT YOU NEED TO GET ON THE INTERNET:
•HARDWARE (perhaps including a modem)
•A WEB BROWSER---Examples: Internet Explorer & Firefox---Function: Helps you access pages on the WWW & sets specifications on how those pages appear.
•AN INTERNET SERVICE PROVIDER
WEB BROWSERS
Internet Explorer
Mozilla Firefox
SOME BROWSER BUTTONS
Internet Explorer
Mozilla FirefoxRefresh
Favorites/Bookmarks
BackStop
Forward
Internet Use as Risen Steadily Since 1997
Now in U.S. approximately 75%
COMMON INTERNET USES
Social Networks—Facebook, Twitter, etc.
On-Line Games
Classifieds/Auctions
Information Search
Videos/Movies—YouTube, Netflix, etc.
E-MAIL ETIQUETTE
1. Be sure to include a Subject Line.
2. Use BCC to avoid giving out others’ e-mail addresses.
3. Keep messages short & focused.
4. Don’t use ALL CAPS!
5. Use discretion in your content.
6. Use a smiley to avoid being misunderstood.
7. Include your name at the bottom.
SEARCH ENGINES
•Used to locate information on the Internet.
•May have different sections, such as Images & News.
SEARCH ENGINES
Advanced Search options let you look for a specific type of file, a date, a certain language, a particular domain type (.com, .edu), etc.
SEARCH ENGINES
Common Search Engines:Google
Bing
Yahoo
SECURITY THREATS
Virus--A program that attaches itself to a program or file spreading infection when it is sent on. Usually attached to an .exe file & can only spread when a human send it on or opens it.
Worm--A program that spreads from computer to computer causing problems with your computer. It has the capability to travel without any human action. Because it can copy itself it may eventually take up all your computer memory & cause it to stop operating.
SECURITY THREATS
Spyware--A program that originally seems like legitimate software but will do damage when installed on your computer. Can cause serious damage by destroying or deleting files & information.
Phishing—A e-mail that appears to be legitimate from a known company or bank. They ask you to enter personal information and then use it to steal your identity or financial resources.
TIPS TO STAY SAFE 1. Deal with sites that use encryption. This keeps your
information safe by sending it in a coded form.
2. Use anti-virus and anti-spyware software.
3. Be sure your computer has a firewall set.
4. Deal only with companies you know and never give out personal or financial information by e-mail.
5. Only open e-mails from addresses that you know. Be especially careful of .exe files attached to e-mails.
INTERNET BASICS
Happy Computing!