the internet and www. the internet owhat is the internet? oa worldwide collection of networks othe...
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The Internet and WWW
The Internet
o What is the Internet?o A worldwide collection of networkso The Internet backbone is the main collection of
networks that carry information from one place to another (including other countries)
o What are some services found on the Internet?o World Wide Web (WWW)o E-mailo File Transfer Protocol (FTP)o Newsgroupso Chat roomso Instant Messaging
History of the Internet
o Where did the Internet come from?o ARPANET- The original Internet backbone
o Networking project by Pentagon’s Advanced Research Projects Agency (ARPA)
o Goals- To build a network that would-o Allow scientists at different physical locations to share information and work togethero Function if part of network were disabled or destroyed
o Became functional September 1969 and consisted of 4 main computers. Each of those computers acted as a host.
o A host is any computer that provides services and connections to other computers on a network.
ARPANET in 1971
ARPANET in 1980
History of the Internet
How has the Internet grown?
TodayMore than 150 million host nodes
1984More than 1,000 host nodes
1969Four host nodes
History of the Internet
o Who controls the Internet?o No one- it is a public, cooperative, and
independent networko Several organizations set standards
World Wide Web Consortium (W3C)
o Oversees research, sets standards and guidelines
o Tim Berners-Lee, director
Internet2 (I2)
o Internet-related research and development project
o Develops and tests advanced Internet technologies
High-speed/Broadband
High-speed/Broadband
Slow-speed technology
Slow-speed technology
How the Internet Works
How can you connect to the Internet?
Dial-up accessmodem in your computer uses a
standard telephone line to connect to the Internet
Dial-up accessmodem in your computer uses a
standard telephone line to connect to the Internet
Connection is
always on—whenever
the computer is running
Connection is
always on—whenever
the computer is running
Connection must be established each time you log on. Slow but inexpensive
Connection must be established each time you log on. Slow but inexpensive
Digital subscriber line (DSL)- Uses regular copper telephone lines
Cable Modem-
Uses the cable TV network
Fixed wireless-
Antenna on house communicates
with a tower location
Satellite Modem-
Connects via a satellite dish
Digital subscriber line (DSL)- Uses regular copper telephone lines
Cable Modem-
Uses the cable TV network
Fixed wireless-
Antenna on house communicates
with a tower location
Satellite Modem-
Connects via a satellite dish
How the Internet Works
o Access Providerso A business that provides access to the Internet free or for a fee
o Usually a fixed monthly paymento ISP (Internet Service Provider)- EarthLinko OSP (Online Service Provider)- same as ISP, but includes members only features. AOL and
MSN, for example)o WISP (Wireless Internet Service Provider)- T-Mobile, Verizon Wireless
How the Internet Works
o Internet Addresseso The Internet relies on an addressing system to send
data to a computer at a specific destinationo IP Address- Internet Protocol Address
o Four groups of numbers, separated by a period. The number in each group is between 0 and 255.
o Text version of Internet Protocol (IP) address
o Top-level domain- identifies the type of organization associated with the domain name
o The Internet Corporation for Assigned Names and Numbers (ICANN) assigns and controls top-level domains.
o Domain Name System (DNS)o The method that the Internet uses to store
domain names and their corresponding IP addresses
o A DNS server translates the domain name to its associated IP address so that data can be routed to the correct computer.
What is a domain name?
The World Wide Web
o What is the World Wide Web (WWW)?o A service of the Interneto A worldwide collection of electronic documents, also
called the Webo Each electronic document is called a Web pageo Can contain text, graphics, sound, video, and built-in
connectionso A Web site is a collection of related Web pages
The World Wide Web
o What is a Web browser?o Program that allows you to view Web pages
MicrosoftInternetExplorer
Netscape
MozillaFireFox
The World Wide Web
o What is a home page?o The first page that a Web site presents o Often provides connections to other Web pages
The World Wide Web
oHow do handheld computers and cellular telephones access the Web?
o Use a microbrowser that displays Web pages that contain mostly text
o Must be Web-enabled
The World Wide Web
o What is downloading?o The process of a computer receiving informationo Depending upon connection speed, downloading can
take from a few seconds to several minutes
The World Wide Web
oURL (Uniform Resource Locator)- Unique address for a Web page
oA web server delivers the Web page to your computeroHTTP (Hypertext Transfer Protocol)- set of rules that defines how the pages transfer on the Internet
The World Wide Web
o What is a hyperlink (link)?o Built-in connection to another related
Web page locationo Item found elsewhere
on same Web pageo Different Web page
at same Web siteo Web page at a different
Web site
The World Wide Web
o What is a search engine?o Program used to find
Web sites and Web pages by entering words or phrases called search text
o Also called a keywordo Many search engines use a
program called a spider to build and maintain lists of words found on Web sites.
The World Wide Web
o How to effectively use a search engineo Use specific nouns and put the most important terms firsto List all possible spellings (for example, email, e-mail)o Before using a search engine, read its Help infoo Use operators
o Use the space or + operator when you want search results to display hits that include specific words (ex. Art + Music)o Use OR operator when you want search results to display hits that include one word from a list (ex. Dog OR Puppy)o Use minus operator (-) when you want to exclude a word from the search results (ex. automobile –convertible)o Use quotation marks operator when you want to search for an exact phrase (ex. “19th century literature”)o Use asterisk operator (*) when you want search results to substitute characters in place of the asterisk (writer*)
The World Wide Web
o What is a hit?o Any Web site name that is listed as the result of a search
Step 1. Go to search engine
Step 2.Select type of search you wantto run
Step 4. Click link to view Web site
Step 3. View hits
The World Wide Web
o What is a subject directory?o Search tool with organized set of topics and
subtopicso Lets you find information by clicking links rather
than entering keywords
The World Wide Web
o What is multimedia?o Application integrating text
with other media elementso Graphicso Animationo Audioo Videoo Virtual reality
The World Wide Web
o What graphics formats are used on the Web?
BMPBit Map
BMPBit Map
GIFGraphics Interchange
Format
GIFGraphics Interchange
Format
JPEGJoint Photographic
Experts Group
JPEGJoint Photographic
Experts Group
NOT TIFFTagged Image
File Format
NOT TIFFTagged Image
File Format
PNGPortable Network
Graphics
PNGPortable Network
Graphics
The World Wide Web
o What is a thumbnail?o Small version of a
larger graphic image-used to improve Web page display timeoUsually click
on thumbnail to display larger image
The World Wide Web
o What is animation?o Appearance of motion created by
displaying a series of still imagesin sequence
The World Wide Web
o What is audio?o Music, speech, or any other soundo Individual compressed sound files
that you download from the Web to your computer
o Common Web audio file formats are MP3, WAV, WMA (Windows Media Audio), MPEG, RealAudio, and QuickTime
o Once downloaded, you can play (listen to) the contents of the files
The World Wide Web
o What is streaming audio?o Transfers data in a
continuous and even flow
o Enables you to listen to the sound as it downloads to your computer
o Radio stations use streaming audio to broadcast over the Web
The World Wide Web
o What is video?o Consists of full-motion images with sound
played back at various speedso MPEG (Moving Pictures Experts Group)
is popular video compressionstandard
The World Wide Web
o What is virtual reality (VR)?o Use of computers to
simulate real or imagined environment
o Appears as a three dimensional (3-D) space
o Used for games and many practical applications
The World Wide Web
o What are plug-ins?o Programs that
extend the capability of a browser
o You can download many plug-ins at nocost from variousWeb sites
Business to business (B2B)Business providing goods and
services to other businesses
Consumer to consumer (C2C)One consumer sells directly to another
Electronic Commerce
o What is e-commerce?o Short for electronic commerceo Business transaction that occurs over
the Internet
Business to consumer (B2C)Sale of goods to general public
Other Internet Services
o What is e-mail?o Short for electronic mailo The transmission of messages and files via a computer
networko Messages can consist of simple text or can contain
attachments, such as documents, graphics, or audio/video clips
o Internet access providers usually provide an e-mail program
o Some Web sites—such as MSN Hotmail and Yahoo!—provide free e-mail services
o One of the original services on the Internet
Other Internet Services
o What is an e-mail address?o Unique name that consists of a user name
and domain name that identifies the user
Other Internet Services
o How does an e-mail message travel?
Step 1.Using e-mail software, you create and send message
Step 2.Your software contacts software on your ISP’s outgoing mail server
Step 4.When recipient uses e-mail software to check for e-mail messages, the message transfers from incoming mail server to recipient’s computer
Step 3.Software on outgoing mail server determines best route for data and sends message, which travels along Internet routers to recipient’s incoming mail server
Other Internet Services
o What is FTP?o File Transfer Protocol
—Internet standard that allows you to upload and download files with other computers on the Internet
Other Internet Services
o What is a chat?o Real-time typed conversation
that takes place on a computero Chat room is location on
server that permits users to discuss topics of interest
o What is instant messaging (IM)?o A real-time Internet
communications service that notifies you when one or more people are online and allows you to exchange messages or files
Netiquette
o What is netiquette?o Code of acceptable behaviors users should
follow while on the Interneto Golden Rule- treat others as you would like
them to treat youo For email and chat rooms
o Avoid sending spam, or junk mail
o Use meaningful subject lines
o Be careful when using sarcasm or humor, as it might be misinterpreted
o Do not assume material is up-to-date or accurate
Creating a Web Site
Identify the goal of the web site Who is the audience? Create a storyboard
Identify each page in the siteHow are they linked together?
Choose a layout Choose a design
Creating, cont.
Use Dreamweaver to design the site Once the layout is complete, add
content (text, images, etc.)
Publishing the Web Site
When you create a Web site on your computer, it will not be available for other people to see
All of the files for the site have to be published to a Web Serveralpha.lasalle.edu
When viewed, they will be athttp://www.lasalle.edu/~smithj1/file.html
Web Server A Web Server is a computer that runs
special serving software It “serves” the Web site files to the client
when requested When a user opens their browser to view a
Web site, they make a request by entering a URL
When the server recieves the request, it sends/serves the page the user wants to see as well as any related files (images).
HTML Basics HTML is the computer language that
Web pages are written in The Web page itself is just a text
document with instructions for the browser
It tells the browser what text to display on the screen, the location of the files for the images and where to display them, etc.
FrontPage
Open FrontPage!