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History of the Internet Began in 1969 as a network of computers at UCLA, UC @ Santa Barbara, Stanford & Univ. of Utah. It was funded by the U.S Dept. of Defense. The first network was called ARPANET. Reason for Internet The 1st goal was to develop hardware & software needed to create geographically dispersed network that could function even if a network was destroyed or disabled. 2nd goal was to create a way for scientists at different locations to share info & collaborate on military projects What is the Internet? It links computers to computers sharing the TCP/IP protocols. The internet is the transport vehicle for the information stored in files or documents on another computer. The Internet itself does not contain information. Definition of Internet The term Internet, is used to describe a world wide group of connected networks that allow public access to information and services. No single organization owns or controls the Internet. Quote "Too many young people believe if they see it on the Internet, it must be true." Alan November Getting connected to the Internet? To access the Internet you need: – A computer – A modem – Software to dial into an ISP – An ISP (Internet service provider) The World Wide Web 1991 Tim Berners-Lee released a program that allowed you to create a document called a Web page that had built in links to other related documents. The collection of hyperlinked documents on the internet is known as : World Wide Web or WWW or W3 or simply the Web. What is the World Wide Web? Microsoft Explorer or Netscape are the browsers that allow you to view documents on the internet. The current foundation on which WWW functions is Hypertext using HTML. HTML provides highlighted links to other documents What makes “the Web” work? HTML: Hypertext Markup Language This is a standardized language of computer code, imbedded in a”source” documents behind all web documents. The browsers are programmed to interpret HTML for display. HTML can be found in other programming languages & applications such as Javascript, SGML & XML. What makes “the Web” work? URL: Uniform Resource Locator This is the unique address of any web document Anatomy of a URL http://www.utexas.edu/welcome http:// - this is the type of file www.utexas.edu - this is the domain name. Identifies computer that stores the web. /welcome – this is the directory pathidentifies where the web page is stored. What are you really searching? WWW is currently estimated at over 1 billion documents. It is not indexed in any standard vocabulary, unlike a library’s catalogs. The web is the totality of the many web pages which reside on computers called servers all over the world. Domain Owner Why would I want to know who owns a web site? You may want to know who publishes the information you are reading or identify the group that pays for the site. Ownership of a web site can be found by going to alltheweb.com “Searching the Web” It is not possible to search the web directly. Your computer will access one of the several intermediate databases & or webpages which contains selections of other web pages organized to allow you to find other web pages. They provide you with URLs to other pages. Search Tools Search Engines: Alta vista, Hotbot, Lycos, Excite, Dogpile, Metafind These search by keyword, trying to match exact words. Use no browsing & no subject categories Can search from minimal to specialized up to 90+% of the web. Who made money on my search? Search pages like Google, Altavista and Yahoo make money by selling key words to companies Companies pay per click to have their web site listed first in the major search pages. For more information: Alan November’s web site Subject Directories These are hand-selected sites picked by editors. Organized into hierarchical subject categories. Can only search the subject categories & descriptions. Examples are librarian’s indexes, Britannica’s & Yahoo galaxy Subject Guides These are web pages of collections of links on a subject Complied by “expert” subject specialist, agencies & associations Examples are: www virtual library & Argus clearinghouse. Web search strategy Four Steps to search strategy Step 1 Analyze your topic Step 2 Pick the right starting place Step 4 Don't bog down in any strategy Step 3 Learn as you go Vary your approach What not to do! Browsing searchable directories “Simple” searching in large search engine databases. Following links to sites recommended by popular vote or commercial interest. Hoax Web Sites Boilerplate: http://www.bigredhair.com/boilerplate.html California's Velcro Crop under Challenge: http://home.inreach.com/kumbach/velcro.html Mankato, Minnesota: http://lme.mnsu.edu/mankato/mankato.html The Onion http://www.theonion.com/3939/ Recognizing Domain Types ..edu a U.S. college or university .com a commercial, for-profit entity .orga non-commercial, non-profit entity .gov U.S. government .milU.S. military .net a computer network .int an international organization .jp, .ru, .ca, .au, etc. country identifiers