MODULE 6 THE INTERNET
Dec 24, 2015
MODULE 6
THE INTERNET
Introduction to the Internet and World Wide Web
• A computer network is a communication system that connects two or more computers so that they can exchange information and share resources.
• A network can be set up in different arrangement to suit users’ needs.
Types of networks
• Local Area Network• Metropolitan Area Network• Wide Area Network
Local Area Network (LAN)
• A local area network (LAN) is a network with nodes that are in close physical proximity—within the same building for instance.
• Node—any device that is connected to a network. It could be a computer, printer, or data storage device.
• Typically, LANs span distances less than a mile and are owned and operated by individual organizations.
LAN
Types of LANs
• Home Networks is a LAN for home and apartment use; typically wireless.
• Wireless LAN (WLAN) is a LAN where all communication passes through access point.
• Personal Area Network is a LAN that connects digital devices such as PDAs.
Metropolitan Area Network (MAN)
• MAN spans distances up to 100 miles.• These networks are frequently used as link
between office buildings that are located throughout a city.
Wide Area Network (WAN)
• Wide area networks (WANs) are countrywide and worldwide networks.
• These networks provide access to regional services (MAN) providers and typically span distances greater than 100 miles.
• They use microwave relays and satellites to reach users over long distances—for example, from Los Angeles to Paris.
WAN
The Internet
• The Internet is the widest of all WANs, which spans the entire globe.
• The Internet is often referred to as the Information Superhighway.
• In a sense, it is like a highway that connects you to millions of other people and organization.
• Unlike typical highways that move people and things from one location to another, the Internet moves your ideas and information.
cont
• The Web provides an easy-to-use, intuitive, multimedia interface to resources available on the Internet.
• It has become an everyday tool for all of us to use.
• The Internet was launched in 1969 when the United States funded a project that developed a national computer network called ARPANET.
The Web
• The Web provides an easy-to-use, intuitive, multimedia interface to resources available on the Internet.
• The Web was introduced in 1991 at the CERN in Switzerland.
• Prior to the Web, the Internet was all text―no graphics, animations, sound, or video.
• The Web made it possible to include these elements.
cont
• The first generation of the Web, known as Web 1.0, focused on linking existing information.
• In 2001, the second generation, Web 2.0, evolved to support more dynamic content creation and social interaction.
• Facebook is one of the best known Web 2.0 applications.• Some suggest that we have entered into the next
generation, Web 3,0. • It focuses on computer-generated information requiring
less human interaction to locate and to integrate information.
Uses of the Internet and the Web
• Communicating • Shopping• Searching for information• Education or e-learning• Entertainment
Accessing the Internet and the Web
• The most common way to access the Internet is through an Internet Service Provider (ISP).
• ISPs in Zanzibar are Zanlink, Zantel, Zanzibar Connect, Tigo, Airtel and Vodacom.
• When provided with a connection to the Internet, you can use a browser program to search the Web.
• Users connect to ISPs using one of a variety of connection technologies including DSL, cable, and wireless modem.
cont
• Browser• URLs• Domain name• HTML• Web page
Browsers
• Browsers are programs that provide access to Web resources.
• This software connects you to remote computers, opens and transfer files, displays text, images, and multimedia, and provides in one tool an uncomplicated interface to the Internet and Web documents.
• Four well-known browsers are Mozilla Firefox, Apple Safari, Microsoft Internet Explorer, and Google Chrome.
URL
• Uniform Resource Locator (ULR) is a web address of the resource.
• http://www.suza.ac.tz• http represent the protocol used for Web
traffic.• Protocols are rules for exchanging data between
computers.• www.suza.ac.tz represents the domain name of
the organization.
cont
• It indicates the specific address where the resource is located.
• ac indicates an academic site.• tz indicates the site is in Tanzania.
HTML
• Web documents must be writing using the Hypertext Markup Language (HTML).
• The browser interprets the HTML formatting instructions and displays the document as a Web Page.
Electronic Mail
• E-mail—provides a fast, efficient alternative to traditional mail by sending and receiving electronic documents.
• E-mail is the transmission of electronic messages over the Internet.
• [email protected]• Web email for example yahoo.com,
hotmail.com or google.com.
Search Engines
• Search engines are specialized programs that assist you in locating information on the Web and the Internet.
• Example is Google’s search engine.
Electronic Learning Tools
Features Available in Student Registration System (Zalongwa)