Discovering Computers 2010 Chapter 2 The Internet and World Wide Web

The Internet Also the Net Worldwide collection of networks Services on the Internet Two of the Mostly widely used services World Wide Web (WWW) Email Other services Chat rooms Instant Messaging VoIP (Voice over Internet Protocol) Next

Evolution of the Internet How did the Internet originate? ARPANET Networking project by Pentagon’s Advanced Research Projects Agency (ARPA) Goal: To allow scientists at different locations to share information Goal: To function if part of network were disabled Became functional September 1969 Next

Evolution of the Internet How has the Internet grown? Today More than 550 million host nodes 1984 More than 1,000 host nodes 1969 Four host nodes (provide services and connection to others on a network (UCLA, UCSB, Stanford, Utah) Next

Evolution of the Internet National Science Foundation (NSF) In 1986 connected its huge network of five supercomputers (NSFnet) to ARPANET Became known as the Internet Until 1995, handle the bulk of the communication activity In 1995, terminated its network on the Internet and resumed its status as a research network

Evolution of the Internet Who controls the Internet? No onec—cit is a public, cooperative, and independent network Several organizations set standards World Wide Web Consortium (W3C) Oversees research, sets standards and guidelines Mission is to contribute to the growth of the Web Nearly 400 organizations around the world are members of the W3C Next

Internet 2 Not-for-Profit research and development project that connects universities and companies via a high –speed private network Goals was to develop and test advanced network technologies that will benefit Internet users in the short-term future Some projects that are now mainstream includes: Telemedicine and digital libraries

How the Internet Works How can you connect to the Internet? High-speed connection Broadband Internet service Cable, DSL, fiber, radio signals, and satellite Connection is always on— whenever the computer is running 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. Next

Connecting to the Internet DSL (digital subscriber line) – use the regular copper telephone lines Fiber to the Premises(FTTP) – use fiber-optic cable Fixed wireless – use dish-shaped antenna on the house or business Cellular radio network – use built-in compatible technology or computers with wireless modems Wi-Fi (wireless fidelity) – uses radio signals Satellite Internet service – use satellite to satellite dish

How the Internet Works What are ways to access the Internet? An access provider is a business that provides individual and organization access to the Internet free or for a fee. Three Categories: ISP, Regional or National (AT&T and EarthLink) OSP (AOL and MSN, two more popular) Wireless Internet Service Provider (ex. AT&T, Boingo Wireless, Sprint Broadband Direct, T-Mobile, and Verizon Wireless) Next

How the Internet Works What is a IP address? Internet protocol address Number that uniquely identifies each computer or device connected to Internet Consists of four groups of numbers, each separated by a period Number between 0 and 255 The first portion of each IP address identifies the network and the last portion identifies the specific computer Next

How the Internet Works What is a domain name? Text version of Internet protocol (IP) address The text in the domain name up to the first period identifies the type of Internet server. The last section contains the top-level domain (identifies the type of organization) ICANN – assigns and controls top-level domains Next

The World Wide Web What is the World Wide Web (WWW)? Emerged in the early 1990s A worldwide collection of electronic documents Also called the Web Each electronic document is called a Web page Can contain text, graphics, audio, video, and built-in connections A Web site is a collection of related Web pages Next

The World Wide Web What is a Web browser? Program that allows you to view Web pages The more widely used Web browsers for PC are: Internet Explorer Google Chrome Firefox Opera Safari Next

The World Wide Web What is a home page? The first page that a Web site displays Often provides links to other documents, Web pages or Websites A link, short for hyperlink, is built-in connection to another related Web page or part of a Web page Next

The World Wide Web How do Internet-enabled mobile devices access the Web? Use a microbrowser that displays Web pages that contain mostly text Next

The World Wide Web What is downloading? The process of a computer receiving information Depending upon connection speed, downloading can take from a few seconds to several minutes Next

World Wide Web What is a URL? Unique address for a Web page Consist of a protocol, domain name and sometimes the path to a specific Web page or location on a Web page. Many web page addresses begin with http:// (a set of rules that defines how pages transfer on the Internet Not required A web server delivers the Web page to your computer Next

The World Wide Web How do you Navigate Web Pages? Hypertext – refers to links in text-based documents Hypermedia – combines text-based links with graphic, audio, and video links Some people use the phrase, surfing the Web, to refer to the activity of using links to explore the Web. Tabbed browsing – top of the browser displays a tab for each Web page you open.

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

The World Wide Web How do you Search the Web? Primary reason that people use the Web is to search for specific information. There are two types of search tools Search Engines Subject Directories

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 Each word in the search text is known as a keyword. Hits are the results of an search. Next

The World Wide Web What is a subject directory? Search tool with organized set of categories and subcategories Lets you find information by clicking links rather than entering keywords Major disadvantage is that users have difficulty deciding which categories to choose. Next

The World Wide Web What are the thirteen basic types of Web sites? Portal News Informational Blog Wiki Online Social Network Educational Entertainment Advocacy Web Application Content Aggregator Personal

The World Wide Web What is a portal? A Web site that offers a variety of services from one, convenient location, usually for free Searching, news, sports and weather, Web publishing, reference tools, stock quotes, maps, shopping, e-mail, and online communities (Web sites that join people with similar interests) Next

The World Wide Web What is a news Web site? Contains newsworthy material Stories and articles relating to current events, life, money, sports, and the weather Next

The World Wide Web What is an informational Web site? Contains factual information Created by organizations and government agencies Next

The World Wide Web What is a business/marketing Web site? Contains content that promotes or sells products or services Allows you to purchase products or services online Next

The World Wide Web What is a blog? Short for Weblog An informal website consisting of time-stamped articles or posts, in a diary or journal format Uses a regularly updated journal format to reflect the interests, opinions, and personalities of the author and sometimes site visitors Blogger – author of a blog Next

The World Wide Web What is a wiki? Collaborative Web site that allows users to create, add to, modify, or delete the Web site content via their Web browser Are open to modification by the general public Difference between a wiki and blog is that users cannot modify original posts made by the blogger. Popular wiki - Wikipedia

The World Wide Web What is an online social network? Encourages members to share their interests, ideas, stories, photos, music, and videos Popular social networking sites include Facebook and MySpace. Media sharing Web site Share photos, music, and videos Next

The World Wide Web What is an educational Web site? Offers avenues for formal and informal teaching and learning Learn how airplanes fly or how to cook a meal Some colleges offer online classes and degrees Next

The World Wide Web What is an entertainment Web site? Offers an interactive and engaging environment featuring music, videos, sports, games, ongoing Web episodes, sweepstakes, chats, and more Next

The World Wide Web What is an advocacy Web site? Contains content that describes a cause, opinion, or idea Next

The World Wide Web What is an Web Application Web site? Allows users to access and interact with software through a Web browser on any computer or device that is connected the Internet Next

The World Wide Web What is a content aggregator? Business that gathers and organizes Web content and then distributes, or feeds, the content to subscribers for free or a fee Next

The World Wide Web What is a personal Web site? Web page maintained by private individual or family Reasons: sharing life experience with the world or job hunting Next