What is the Internet?What is the Internet?11/27/0711/27/07

Where did the Internet start?Where did the Internet start?

Networked computers started by MilitaryNetworked computers started by Military ARPANET – 1969 experiment by the ARPANET – 1969 experiment by the

Defense departmentDefense department During war email part became popularDuring war email part became popular Soon became a problemSoon became a problem Protocols were developedProtocols were developed Evolved into today’s InternetEvolved into today’s Internet

World Wide WebWorld Wide Web

Internet went unnoticed for several Internet went unnoticed for several decadesdecades

1989 – Tim Berners-Lee proposed an idea 1989 – Tim Berners-Lee proposed an idea at CERN (a physics lab in Europe)at CERN (a physics lab in Europe)

Envisioned a network to organize info in Envisioned a network to organize info in pages that were connected by selectable pages that were connected by selectable text – hyperlinkstext – hyperlinks

Became popular with researchersBecame popular with researchers

1993 – Graphical User 1993 – Graphical User Interface was Interface was introducedintroduced

Mosaic released as 1Mosaic released as 1stst graphical web browsergraphical web browser

Web is only part of the Web is only part of the internetinternet

Internet Service ProvidersInternet Service Providers

Who we get our service fromWho we get our service from For a feeFor a fee

Examples: ATT, AOL, Sprint, EarthLink, Examples: ATT, AOL, Sprint, EarthLink, Comcast CableComcast Cable

Provide access to World Wide Web, email, Provide access to World Wide Web, email, other resourcesother resources

Content ProvidersContent Providers

Supply info to InternetSupply info to Internet Commercial businessesCommercial businesses Nonprofit organizationsNonprofit organizations Educational institutions Educational institutions IndividualsIndividuals

Application Service ProvidersApplication Service Providers

Companies that manage/distribute Companies that manage/distribute software-based servicessoftware-based services

Rent software access Rent software access Examples: office suites, accounting Examples: office suites, accounting

programsprograms Web ServicesWeb Services

Infrastructure CompaniesInfrastructure Companies

Enterprises that own/operate paths of the Enterprises that own/operate paths of the InternetInternet

Telephone, satellite, and cable companiesTelephone, satellite, and cable companies

Hardware/software companiesHardware/software companies

Companies that make/distribute products Companies that make/distribute products used with internetused with internet

How do I find info?How do I find info?

Internet AddressesInternet Addresses

IP address – Internet Protocol addressIP address – Internet Protocol address Uniquely identifies each computer or Uniquely identifies each computer or

devicedevice ExampleExample

216.239.39.99216.239.39.99

Identifies specific computer

Domain NameDomain Name

IP hard to rememberIP hard to remember Domain name – text versionDomain name – text version

www.google.comwww.google.com Examples of domain names:Examples of domain names:

Com - commercialCom - commercial Edu - educationEdu - education Gov - governmentGov - government Mil - militaryMil - military Net – network providerNet – network provider Org – non-profit organizationOrg – non-profit organization

Web AddressesWeb Addresses

URL – Uniform Resource LocatorURL – Uniform Resource Locator http://www.us-parks.com/grand_canyon/http://www.us-parks.com/grand_canyon/

scenic_vistas.htmlscenic_vistas.html http: - Hypertext Transfer Protocol – sets rules http: - Hypertext Transfer Protocol – sets rules

how pages transfer on the Internethow pages transfer on the Internet www.us-parks.com – domain namewww.us-parks.com – domain name grand_canyon – path to the servergrand_canyon – path to the server scenic_vistas.html – web page namescenic_vistas.html – web page name