Chapter 11 The Internet and World Wide Web

The Internet These services are found on the Internet (How many do you use? How often do you use these services? Do you expect to use them more or less in the future?) 4. Chat (4) (1) 1. (2) 2. Web (3) 3. File transfer (5) 5. Message board (6) 6. Instant messaging

History of the Internet Origin of the Internet Goal: To function if part of network were disabled Became functional September 1969 ARPANET Networking project by Pentagon’s Advanced Research Projects Agency (ARPA) Goal: To allow scientists at different locations to share information Robustness was a key concern for early Internet developers

History of the Internet Growth of the Internet Today More than 150 million host nodes 1984 More than 1,000 host nodes 1969 Four host nodes

History of the Internet Controls of the Internet World Wide Web Consortium (W3C)  Oversees research, sets standards and guidelines  Tim Berners-Lee, director Internet2 (I2)  Internet-related research and development project  Develops and tests advanced Internet technologies  No central control c — c it is a public, cooperative, and independent network  Several organizations set standards  Adherence to these standards makes the Internet work World Wide Web Consortium (W3C)  Oversees research, sets standards and guidelines  Tim Berners-Lee, director

High-speed connection Slow-speed technology How the Internet Works Types of Internet Connection Dial-up access modem in your computer uses a standard telephone line to connect to the Internet Digital subscriber line (DSL), cable telephone Internet services (CATV), cable modem provide connections using regular copper telephone lines Connection is always on— whenever the computer is running Connection must be established each time you log on. Slow but inexpensive ADSL

How the Internet Works Services used to access the Internet. 1. ISP, Internet Service Provider (Connection, server & limited web hosting) (Regional or National) 2. OSP, Online Service Provider (More extensive services) (AOL and MSN, for example) 3. WISP, Wireless Internet Service Provider User pays for time &/or download

How the Internet Works How data travels the Internet using a telephone line connection Step 1. Request data from a server on Internet Step 5. Regional ISP uses leased lines to send data to a national ISP Step 6. National ISP routes data across the country Step 8. Server sends data back to you Step 2. Modem converts digital signals to analog signals Step 3. Data travels through telephone lines to a local ISP Step 4. Data passes through routers Step 7. National ISP passes data to local ISP

How the Internet Works What is a domain name?  Text version of Internet protocol (IP) address  IP Address is the Number that uniquely identifies each computer or device connected to Internet  IP address is essential for sending and receiving data

The World Wide Web What is the World Wide Web (WWW)? A worldwide collection of electronic documents Each electronic document is called a Web page Also called the Web Can contain text, graphics, sound, video, and built-in connectionsA Web site is a collection of related Web pages

The World Wide Web What is a Web browser? Microsoft Internet Explorer Netscape Mozilla  Program that allows you to view Web pages Firefox If you access the internet regularly, What browser do you use and why?

The World Wide Web Establishing an internet connection and starting the Web browser Step 2. If necessary, connect to the Internet Step 3. Connection to the Internet occurs, and a home page displays Step 1. Click the Web browser program name

The World Wide Web What is a home page?  The first page that a Web site presents  Often provides connections to other Web pages You can change your home page using Tools/Options in the Browser Window

The World Wide Web  Handheld devices use a microbrowser that displays Web pages that contain mostly text  They must be Web- enabled to be able to connect to the internet themselves or via another device (eg. Mobile Phone) Web-enabled Handhelds Devices

The World Wide Web Downloading is:  The process of a computer receiving information  Depending upon connection speed, downloading can take from a few seconds to several minutes  Connection Speed is often referred to as Bandwidth

The World Wide Web A URL also known as a Universal Resource Locator is: Unique address for a Web page  URL identifies the webpage that you want to see.  A web server delivers the Web page to your computer  URL has several parts  Protocol (HTTP, FTP)  Domain Name (Server file want is on)  Directories (Folders?)  Name of File you want

The World Wide Web A hyperlink (link) is: It specifies the location of  An Item found elsewhere on same Web page  A Different Web page at same Web site  A Web page at a different Web site  Built-in connection to another related Web page location

The World Wide Web How can you recognize links on a Web page?  A link can be text or an image  Some image links look like buttons  Pointer changes to a small hand when you point to a link  Text links are usually underlined and in a different color

The World Wide Web A search engine is:  Program used to find Web sites and Web pages by entering words or phrases called search text  The Search Text is also called a keyword  The ability to search the internet effectively is very useful  We cover more about searching in the first Practical Ask others in your area of interest about which search engines they find most useful.

The World Wide Web The results returned by a search engine are referred to as hits Step 1. Go to search engine Step 2. Select type of search you want to run Step 4. Click link to view Web site Step 3. View hits  Any Web site name that is listed as the result of a search Each hit has -a short note about the web resources found, -a link to the resource, -a score for its relevance

The World Wide Web A subject directory is:  Search tool with organized set of topics and subtopics  Lets you find information by clicking links rather than entering keywords A Subject Directory may be very useful if you do not know exactly what you are looking for

The World Wide Web There are eight basic types of Web sites  Portal  News  Informational  Business/marketing  Educational  Entertainment  Advocacy  Personal

The World Wide Web A portal is:  A Web site that offers a variety of services from one, convenient location, usually for free  Searching, sports, , news, weather, auctions, Web communities (Web sites that join people with similar interests)

The World Wide Web A news Web site:  Contains newsworthy material  Stories and articles relating to current events, life, money, sports, and weather News.com.au Has a daily subscription service tha sends daily of news headlines (with brief summaries and links to a nominated address Other similar sites?

The World Wide Web An informational Web site:  Contains factual information  Created by organizations and government agencies

The World Wide Web A business/marketing Web site:  Contains content that promotes products  Allows you to purchase products or services online

The World Wide Web An educational Web site:  Some companies offer online training for employees  Some colleges offer online classes and degrees  Offers avenues for formal and informal teaching and learning

The World Wide Web An entertainment Web site:  Offers an interactive environment featuring music, video, sports, games, and more

The World Wide Web An advocacy Web site:  Contains content that describes a cause, opinion, or idea

The World Wide Web A personal Web site:  Web page maintained by private individual  Reasons: sharing life experience with the world or job hunting

The World Wide Web What is multimedia?  Application integrating text with other media elements  Graphics  Animation  Audio  Video  Virtual reality Multimedia topics are covered in more depth later in the semester

The World Wide Web What graphics formats are used on the Web? BMP GIF (pronounced JIFF) JPEG (pronounced JAY-peg) PCX PNG (pronounced ping) TIFF

The World Wide Web A thumbnail is: Next  Small version of a larger graphic image c —used to improve Web page display time  Usually click on thumbnail to display larger image

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 is:  Music, speech, or any other sound  Individual compressed sound files that you download from the Web to your computer  Common Web audio file formats are MP3, WAV, WMA (Windows Media Audio), MPEG, RealAudio, and QuickTime  Once downloaded, you can play (listen to) the contents of the files

The World Wide Web Streaming audio is when data is transferred in a continuous and even flow  It enables you to listen to the sound as it downloads to your computer  Radio stations use streaming audio to broadcast over the Web

The World Wide Web What is video?  Consists of full-motion images with sound played back at various speeds  MPEG (Moving Pictures Experts Group) is popular video compression standard

The World Wide Web Virtual reality (VR) is when computers are used to simulate real or imagined environment  Images etc appears as a three dimensional (3-D) space  Used for games and many practical applications

The World Wide Web Plug-ins are:  Programs that extend the capability of a browser  You can download many plug-ins at no cost from various Web 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 What is e-commerce? Business to consumer (B2C) Sale of goods to general public  Short for electronic commerce  Business transaction that occurs over the Internet