Introducing the World Wide Web History and Structure

Competencies Covered Standard 1.0Demonstrate knowledge of the Internet and various terms, tools, and utilities associated with the World Wide Web.  1.1 Illustrate the relationship of Web related terms to Web design and software applications. Standard 8.0Examine characteristics, components, and functions of basic network designs.  8.1 Illustrate how computers are connected (both wireless and physical) to form a local area network (LAN).  8.2 Differentiate between peer-to-peer and server-based networks.  8.3 Examine considerations involved in implementing servers in peer-to-peer and server-based networks.

I CAN... Define Web design terms Draw an example of a LAN Draw an example of a WAN List advantages of Peer-to-peer networks List disadvantages of Peer-to-peer networks List advantages of server based networks List disadvantages of server based networks

Definition of World Wide Web AKA  The “Web”  “Web” Define the World Wide Web in your own terms…

Definition of World Wide Web Combination of:  Software  Services  Protocols  Documents

Book Definitions Software that sends information that is stored in files along the Internet’s hardware; A service that uses the Internet to transmit hyperlinked documents; Documents or Web Pages stored on the Internet connected by HTTP

Definition of World Wide Web The complete set of electronic documents stored on computers that are connected over the Internet and are made available by the protocol known as HTTP dictionary.com

Definition of Internet AKA “Net” Define “Internet” in your own terms… basics/ - Videos basics/

Book Definitions Hardware, such as computers, cables, and telephone wires, that are connected to create a massive worldwide network The global network of computers used for communications (components include , FTP, and the Web) A collection of networks where users gain access to services such as , FTP, etc

Definition of Internet A vast computer network of smaller networks connected to create a large network that uses network protocols to facilitate data exchange

Differences World Wide Web and Internet are NOT the same  World Wide Web – documents and software (web pages, software, etc)  Internet – interconnected hardware (computers, cables & wires, etc.)

Internet: Collection of Networks Computers that are linked together via a medium  Phone  Cable  Fiber  Satellites, etc.

Internet: Collection of Networks Purposes  Share resources Printers Files

Internet: Collection of Networks Access networks via  Host or a  Node

Intranet A local or restricted communications network  A private network created using WWW software  Used in small or large businesses, college campuses, etc.  May be composed of multiple LANs

Extranet In contrast with intranet  May also be accessed by customers, suppliers, or other approved parties  Extends a private network (intranet)  Provides outsiders authentication or authorization to access a private network  Allows collaboration, project management & builds customer relations

Networks Server  High speed computers  Store information and resources to be shared Clients  Individual computers in a network

Networks LAN  Local Area Network  A network that links computers that are close together or in a single location such as Department Floor Building

Networks WAN  Wide Area Network  Network that connects computers across a wide geographical area such as Buildings across town Cities or even Regions Internet is the largest WAN in existence

Peer to Peer Networking aka P2P Network Both suppliers and consumers of resources Made popular by file sharing systems like Napster Users decide who gets access Designed for a small number of computers (10-15)

Networks Client-Server network  Servers and clients connected together  Servers answer requests from clients  Server is optimized to answer requests quickly  Files are centrally located  Better levels of security  Internet system is based on this type of network

ACTIVITY Find your partner On a clean sheet of paper draw an example of how you think the Internet looks. Remember – the Internet is the largest WAN – made up of smaller LANS  Multiple LANS Server(s) Client(s) Printer(s) Medium(s)

History of the Internet Forerunner of today’s Internet  ARPAnet - Advanced Research Projects Agency Network Established in 60’s for military and scientific use Two network nodes between UCLA and Stanford University  Connected by a phone line

ARPANET Main purpose – to maintain communications in case of a nuclear war or natural disaster  This was tested during the Gulf War when the Iraqis were able to maintain communications Not the Internet we know today  Difficult to navigate – not “user friendly”  Knowledgeable in terms and commands  Complicated interface

Development of the Internet Concept attributed to J.C.R. Licklider  Professor at MIT  1962 described a future “Galactic Network” of linked computers that would enable everyone access to computer resources  Many industry experts considered it a waste of time and did not support his idea  Licklider went to work for ARPA

Creation of WWW Attributed to Tim Berners-Lee Frustrated/Difficult retrieving phone numbers and documents Developed new protocol called Hypertext Transfer Protocol (HTTP)  Enable communication between a client and server

Hypertext Transfer Protocol Protocol (set of rules) used by the Web to transport Web files from a Web Server to a Web browser

Hyperlinks (Links) Parts of hypertext that allow you to jump from one document/topic to another  Another spot in the same document  A completely different document  Your computer  Another computer anywhere in the world

Web Pages & Sites Hypertext documents make up  Web Pages – individual text documents/files created with HTML tags to display properly in a Web browser Web Pages make up  Web Sites – Collection of Web pages with a common theme or purpose

Web Pages & Sites Evolved from simple pages of text only To complex sites with graphics and multimedia to make purchases, download music, get current stock quotes

Hypertext Markup Language (HTML) Code Used to create Web pages

Web Browsers To see web pages – must use Web Browser  Software used to retrieve, interpret, and display Web content on a user’s PC

Text based browsers  First browsers Text only No pictures or graphics  Second generation of browsers Graphical based Support text, pictures, graphics, and sound WEB BROWSERS

MOSAIC Mosaic - world’s first well-known browser Responsible for making the World Wide Web popular Without it – the average person may never have heard of the web Major achievement - Put a graphical user interface (GUI) on the web Linked sites using hypertext

GUI – Graphical User Interface Pronounces “Gooey” Allows users to communicate by clicking on pictures – aka icons Both Windows and Macintosh systems use a GUI interface

Browsers Today Two dominate Web browsers Originally  Netscape Navigator/Communicator  Microsoft’s Internet Explorer Other browsers have caught up  Firefox Browsers are similar on all types of computer systems – Unix, Windows, Macintosh