Chapter 2 The Internet and World Wide Web
Objectives 1. Explain how to access and connect to the Internet 2. Explain how to view pages and search for information on the Web 3. Describe the types of Web sites 4. Identify the steps required for Web publishing 5. Describe the types of e-commerce 6. Explain how e-mail, FTP, newsgroups and message boards, mailing lists, chat rooms, Instant messaging, and Internet telephony work
How did the Internet originate? • • A Networking project started by an agency of US Dept. of Defense Goal: 1. To build a network that allowed scientists at different locations to share information 2. To function if part of network were disabled • • Name: ARPANET [Advanced Research Projects Agency] Became functional September 1969
Who controls the Internet? Ø Ø No one- it is a public, cooperative, and independent network Several organizations set standards World Wide Web Consortium (W 3 C) § Oversees research, sets standards and guidelines
How can you connect to the Internet? Slow-speed technology Dial-up access modem in your computer uses a standard telephone line to connect to the Internet Connection must be established each time you log on. Slow but inexpensive High-speed connection Digital subscriber line (DSL), cable telephone Internet services (CATV), cable modem, fixed wireless, and satellite modems Connection is always on— whenever the computer is running
What is a domain name? § § Text version of Internet protocol (IP) address Number that uniquely identifies each computer or device connected to Internet
What is a Web browser? n Program that allows you to view Web pages Microsoft Internet Explorer Firefox Netscape Opera Safari
The World Wide Web What is a home page? • – The first page that a Web site displays – Often provides connections to other Web pages What is downloading? • – – The process of a computer receiving information Depending upon connection speed, downloading can take from a few seconds to several minutes • What is tabbed browsing? • The top of the browser displays a tab for each Web page you open
The World Wide Web • What is a URL? – Uniform Resource Locator – Unique address for a Web page • What is a hyperlink? – Built-in connection to another related Web page location – Item found elsewhere on same Web page – Different Web page at same Web site – Web page at a different Web site
The World Wide Web • What is a search engine? – Program used to find Web sites and Web pages by entering words or phrases called search text.
The World Wide Web • What is a subject directory? – Search tool with organized set of topics and subtopics – Lets you find information by clicking links rather than entering keywords
The World Wide Web • What are the eleven basic types of Web sites? 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. Portal News Informational Business/Marketing Educational Entertainment Advocacy Blog Wiki Content Aggregator Personal
The World Wide Web • Portal – Website that offers variety of Internet services from a single convenient location. – Like search engine, news, sports, weather etc, web publishing services, shopping, email, maps etc – AOL, Yahoo!, Lycos, MSN etc
The World Wide Web • News – Website contains newsworthy material. – Like current affairs, news, weather, sports etc – CNN, Fox News
The World Wide Web • Informational – Website contains factual information. – Like Govt. Agencies etc – IRS,
The World Wide Web • Business/Marketing – Website contains content that promotes or sells products or services. – Private companies – Amazon
The World Wide Web • Educational – Website offers avenues formal & informal teaching & learning opportunities. – Universities, Online Learning – HCC
The World Wide Web • Entertainment – Website offers interactive & engaging environment. – Like music, videos, sports, games – Shockwave. com
The World Wide Web • Advocacy – Website contains content that describes a cause, opinion or idea. – Of a particular group or association
The World Wide Web • Blog – Short for Web Log. – Informal website consisting of time-stamped articles or posts in a diary or journal format. – Lists opinions, interests of author.
The World Wide Web • Wiki – Collaborative web site that allows users to add, modify or delete content. – Popular one is Wikipedia.
The World Wide Web • Content Aggregator – Business that gathers & organizes content & then distributes or feeds to subscribers for free or a fee. – Technology is RSS (Really simple Syndication) – Major news, stocks websites.
The World Wide Web • Personal – Private individual or family not associated with any organization. – Contains personal information, pictures etc
The World Wide Web • Guidelines for evaluating the value of a website: 1. Affiliation: A reputable institution should support the website without bias in information 2. Audience: should be written at an appropriate level. 3. Authority: list author & appropriate credentials 4. Content: well organized & links should work 5. Currency: information is current 6. Design: pages should download quickly, look is pleasing & easy to navigate 7. Objectivity: little advertisement & free of preconceptions
The World Wide Web • Multimedia: – Application integrating text with other elements like: • • • Graphics, Animation, Audio, Video, Virtual reality Plug-ins
The World Wide Web • Graphic: – Digital representation of non-text information such as drawing, chart, photograph. Different formats: 1. JPEG: (Joint Photographic Experts Group). jpg, . jpe, . jfif 2. GIF: (Graphics Interchange Format). gif works best for images with few distinct colors. – Thumbnail: small version of a larger image used to improve web page display time.
The World Wide Web Animation: – Appearance of motion created by displaying a series of still images in sequence. • Audio: – 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 AA, AAC, AIFF, ASF, MP 3, WAV, WMA, RA, and QT •
The World Wide Web • Streaming Audio: – Transfers data in a continuous and even flow. – 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 • 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: – Use of computers to simulate real or imagined environment – Appears as a three dimensional (3 -D) space • Used for games and many practical applications
The World Wide Web Plug-ins: • – – Programs that extend the capability of a browser You can download many plug-ins at no cost from various Web sites
E-Commerce • • • Electronic Commerce Business transaction that occurs over the Internet 3 types: 1. B 2 C (Business-to-consumer) 2. C 2 C (Consumer-to-consumer) 3. B 2 B (Business-to-business)
E-Commerce • B 2 C – – • C 2 C – – – • Sale of goods & services to general public E. g. : Dell One consumer sells directly to another. Online auction E. g. : e. Bay B 2 B – – Businesses provide goods & services to other businesses Online advertising, recruiting, training
Other internet services • Email – Electronic mail – The transmission of messages and files via a computer network • • Messages can consist of simple text or can contain attachments, such as documents, graphics, or audio/video clips Internet access providers usually provide an e-mail program
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 • FTP – File Transfer Protocol – Internet standard that permits you to upload and download files with other computers on the Internet • Newsgroup – Online area where users discuss a particular subject • Message Boards – Web based discussion group
Other internet services • Mailing List – Group of e-mail addresses given a single name – When a message is sent to the mailing list, everyone on the list receives the message • Chat – Real-time typed conversation that takes place on a computer – Chat room is location on server that permits users to discuss topics of interest
Other internet services • 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 • Internet Telephony – Enables users to speak to other users over the Internet using their computer
Chapter Summary History and structure of the Internet Newsgroups and Message Boards The World Wide Web Chat Rooms and Instant Messaging E-Mail Internet Telephony FTP
Questions?
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