The Internet Web Basics Dr. Dania Bilal IS 587 Fall 2007

The Internet Beginning –Internet without content –Used for and FTP –Internet with content Usenet newsgroups Directory: Gopher

Gopher Menu-driven content Used by universities Gopher was indexed by –Jughead –Veronica

WWW 1991, Tim-Berners Lee created WWW GUI interface Hypertext navigation of content Multimedia (text, sound, graphics) 1995, Web has become popular and search engines were developed

Web Web interfaces took over text-based interfaces such as ftp Search engines spread Web directories Search engines have become portals –Multi-functions

Internet History See Timeline in Text, chap. 1 See URLs for Internet history and growth, chap. 1 – ks.html#chap1http:// ks.html#chap1

Searching the Web General search engines Specialized search engines Engines vs. portals Meta-search engines Directories Meta-directories All is found at age=

Use of Engines & Directories Engines –To search by keyword, phrase, etc. –Topic is specific –Complex searches Lots of information is retrieved Searching is done in billions of pages Directories –To browse by categories From broad to specific –Simple searches Less information is retrieved Searching is done in millions of pages

Basic Search Strategy Identify information need Extract basic concepts Formulate strategy using concepts and appropriate search parameters –Boolean, proximity, search limiting, as appropriate Select appropriate engine, directory, meta- engine, or meta-directory

Basic Search Strategy Conduct the search (pay attention to spelling) Examine first page of results for relevance Revise search based on results retrieved If not satisfied, use another search engines or directory Note: Meta-engines and meta-directories are used when lots of information is needed for research purposes.

The Question of Quality Criteria for evaluating information quality –Source domain (.com,.edu,.gov, etc.) –Authority –Purpose or motivation –Quality of writing –Balanced views –Currency of information –Sources cited

The Question of Quality Accuracy Factual information (check against two or more authoritative sources) –Currency ernet/Evaluate.html (content quality and design/navigation)

The Invisible Web Search engines don’t index all web pages Reasons: –Page are password-protected –Pages are too deep (too much to index) –Pages not picked up by spiders or crawlers See sites for finding information on the IW in Text.

Overview of Web 2.0 Web 2.0: The machine is us/ing usvideo found at –Search under Web 2.0 (video) What is web 2.0 (video) –Definition, characteristics of Web 2.0, and other information