The Internet and World The Internet and World Wide WebWide Web

Ilona Kane

The InternetThe Internet A worldwide collection of networks that links

millions of businesses, government agencies, educational institutions, and individuals.

Internet’s Resources– Access to information and research– Communicate with others around the world– Bank, Shop, Download music and movies– Access other computers and exchange files

History of the InternetHistory of the Internet Started by the Pentagon’s networking

project known as the Advanced Research Projects Agency (ARPA)

ARPA is an agency of the U.S. Department of Defense whose goal was to create a network that:

– Allowed scientists at different locations to share information and work together on military and scientific projects

– Could function even if part of the network were disabled or destroyed by a disaster such as a nuclear attack

This network is known as the ARPANET

ARPA underwent phenomenal growth as researchers realized the great benefit to sharing information

In 1986, the National Science Foundation, (NSF) connected its huge network of five supercomputer centers, called NSFnet to ARPANET forming the complex networks and hosts known as the Internet today

The Internet traffic today is handled by a variety of corporations and commercial firms, who along with telephone, cable, and satellite companies contribute to the internal structure of the internet.

How the Internet WorksHow the Internet Works Internet Service Providers

– Is a business that has a permanent Internet connection and offers temporary connections to individuals and companies free or for a fee

– 2 major types: Regional ISP- provides access to the

Internet through one or more telephone numbers local to a specific geographic area

National ISP- a larger business that provides local telephone numbers in major cities and towns nationwide

Online Service provider- supplies Internet access, but has many members-only features that offer a variety of special content and services such as weather, games, and travel guides

Wireless Service Provider- provides wireless Internet access to users with wireless modems or Web-enabled computer devices

Connecting to the InternetConnecting to the Internet1. Dial-up access

1. Provides an easy and inexpensive way for users to connect to the Internet

2. Uses a computer, a modem, and a regular telephone line to dial into an ISP or OSP

3. Slow-speed technology

2. Digital Subscriber Line (DSL)1. Provides high-speed connections over a regular copper

telephone line

3. Cable Modem1. Provides high-speed Internet connections through the

cable television network2. Along with DSL costs 2xs as much as dial-up

How Data Travels How Data Travels the Internetthe Internet

Connection to the Internet is a transfer of data around the world using servers and clients

Server- computer that manages the resources on a network and provides a central storage area for resources such as programs and data

Client- a computer that can access the contents of the storage area on a server

IP Address- (Internet Protocol Address) is a number that uniquely identifies each computer or device connected to the Internet

Domain name- the text version of an IP address

DNS server- translates the domain name into its associated IP address, so data can route to the correct computer

Internet AddressesInternet Addresses

The World Wide WebThe World Wide Web Consists of a worldwide

collection of electronic documents, also known as Web pages

A collection of related Web pages- Web Site

Browsing the WebBrowsing the Web

Web browser- a software program that allows you to access and view Web pages– Most widely used:

Microsoft Internet Explorer Netscape

Home page- starting page for a browser– Provides information about the Web site’s purpose and

content Hyperlink- (link) a built-in connection to another

related Web page or part of a web page

Uniform Resource LocatorUniform Resource Locator

Is a Web page’s unique address– Tells the browser where to locate the document– Makes it possible for you to navigate using links

Typical URL: http://www.lasalle.edu/students/home.htm– http = protcol– www.lasalle.edu = domain name– /students/home.htm = path

Search EnginesSearch Engines

Is a software program you can use to find Web sites, Web pages, and Internet files– Are specifically useful

when the exact URL is not known

– Common Search Engines include:

Dogpile, Excite, Yahoo, Google, Lycos

Sources: dogpile.com, excite.com, yahoo.com, google.com, lycos.com

Types of WebTypes of Web PagesPages

1. Portal Web Page- offers a variety of Internet services from a single convenient location

1. Offer search engine2. News reports3. Weather4. Personalized web pages5. Email6. Chat rooms

2. News Web Page- contains news worthy material including stories and articles relating to current events, life, money, and sports

More Web PagesMore Web Pages3. Informational Web Page- contains factual

information such as census data, tax codes, published research findings

4. Business/Marketing Web Page- contains content that promotes or sells products or services

– Such companies include: AT&T, and the Disney Co.

5. Advocacy Page- acts as a device to convince the reader of the validity of the content that describes a cause, opinion, or idea

6. Personal Web Page- established by a private individual who normally is not associated with any organization

– To use for job hunting or to share life experiences

Multimedia on the WebMultimedia on the Web

Graphics- a digital representation of information such as a drawing, chart, or photograph

Animation- the appearance of motion created by displaying a series of still images in a rapid sequence– Makes pages more visually interesting

and draws attention Audio- music, speech, or any other

sounds– MP3 is a popular technology that

compresses audio– Streaming- the process of transferring

data in a continuous and even flow Important because most users do not have a

fast enough Internet connection

Any application that integrates texts with one or more of the following elements: graphics, sound, video, and virtual reality

More MultimediaMore Multimedia

• Video- images that are played back at various speeds– Consist of individual video files, such as movies or TV

clips, that you download– Web cam- a video camera whose output displays on a

Web page• Virtual Reality- the use of computers to simulate a

real or imagined environment that appears as a 3D space– Often used for scientific models, architectural layouts,

and games

WebcastingWebcasting Pull Technology

1. Method of obtaining information which relies on a client such as your computer to request a Web page from a server

2. Example: enter a URL or click a link

Push Technology1. a server automatically

downloads content to your computer at regular intervals or whenever updates are made to the site

2. Example: current sporting event scores displayed on your desktop

Webcasting – uses pull technology, push technology and/or streaming media to deliver information at regualr intervals without you having to request it, or to deliver live recorded sound and video broadcast to your computer

Creating a Web SiteCreating a Web Site Web page authorizing

– Involves working on the computer to compose the Web site1. Word processing packages help create basic web pages that

contain text and graphics2. Web page authorizing software

Is specifically to help create a web page Used to create more sophisticated web pages that include animation,

video, and sound

3. When using a word processing or Web page authorizing software, the Web page is saved in Hypertext Markup Language (HTML) Is a set of special codes that format a file for use on a web page

Deploying and Maintaining a Deploying and Maintaining a Web SiteWeb Site

Store a created Web page on a Web server– Many ISPs and OSPs provide their customers with a Web

address and storage space for the Web site– Web hosting Services- provide storage for your Web site

for a monthly fee Upload the Web site- copy it from your computer to

the Web server Submission Service- a Web-based business that

offers a registration package in which you pay to register with hundreds of search engines

Webmaster- the individual responsible for maintaining a Web site and developing Web pages

E-mailE-mail The transmission of messages and files via a

computer network One of the original services of the Internet Email address- combination of user name and

domain name that identifies a user Address Book- program in email that a contains a

list of names and email addresses Mailbox- a storage location usually residing on

the computer that connects you to the Internet

Web-based GroupsWeb-based Groups

Message Board- type of discussion group, also known as a discussion board

Mailing Lists- a group of e-mail names and addresses

Chat rooms- a location on the Internet server that allows a real-time conversation to take place on a computer

Instant Messaging- a real-time Internet communications service that notifies you when one or more people are online and allows you to exchange messages or files

SourcesSources Discovering Computers 2003 Web sites-

– Aol.com– Dogpile.com– Excite.com– Google.com– Lycos.com– Msn.com– Yahoo.com