1. Search Engines and Subject Directories

2. Search Engines Automated Travel the entire open web When web page changes, search engines will eventually spot changes

3. How Search Engines Work Search engine software  Accepts your search term  Finds matching pages Importance of Search Terms Will only find webpages that match the words you give it Can NOT understand questions or “comments”

4. Search Engine Ranking Three factors  How “relevant” is it?  How popular is it?  Some people play with the system Sponsored links – paid advertising

5. Search Engines – Pros and Cons Pros  Vast amount of information collected  Updated frequently Cons  Sponsored links  Post-search targeted advertising  “Google bombing” can distort results

6. Popular Search Engines AskJeeves (http://www.askjeeves.com)http://www.askjeeves.com Lycos (http://www.lycos.com)http://www.lycos.com Google (http://www.google.com)http://www.google.com Yahoo (http://www.yahoo.com)http://www.yahoo.com Dogpile (http://www.dogpile.com)http://www.dogpile.com Hotbot (http://www.hotbot.com)http://www.hotbot.com Alta Vista (http://www.altavista.com)http://www.altavista.com Vivisimo (http://www.vivisimo.com)http://www.vivisimo.com

7. Subject Directories Human-powered Humans review, select, categorize web sites Changes to a site will not affect its listing on a directory

8. How Subject Directories Work Humans decide on a set of categories Humans review web sites (sometimes based on suggestions from users) Humans assign a site to a category Sometimes humans write actual content

9. Subject Directories Ranking No relevance ranking Humans put categories in order Sites usually listed alphabetically Sponsored links

10. Subject Directories – Pros and Cons Pros  Human review/intervention  Sites are organized by topic  Sites can’t artificially inflate their relevance Cons  Very limited content  Only updated when humans find time

11. Popular Subject Directories Yahoo Directories (http://dir.yahoo.com)http://dir.yahoo.com About.com (http://www.about.com)http://www.about.com Librarian’s Index to the Internet (http://lii.org)http://lii.org Google Directories (http://directory.google.com)http://directory.google.com Infomine (http://www.infomine.ucr.edu)http://www.infomine.ucr.edu LookSmart (http://www.looksmart.com)http://www.looksmart.com

12. So Which Do I Use? Search engine  You already have a very specific topic  You have a very new topic/need very latest info  You need quick facts Subject directory  You have a broad topic and want to narrow it down  You aren’t sure how to get more specific

13. Important Points No search engine will search the entire web Some pages will never be indexed no matter what (“hidden” or “invisible” web) Different search engines and subject directories will give different results Try several to get a good range of results

14. Searching Tips Boolean Searching Phrase Searching Keyword Searching Subject Searching

15. Boolean Searching Used to help make your search more specific or broader Can be used in most searches including:  Web: Search Engines/Subject Directories  Library Catalogs  Databases

16. Boolean Operators AND  Will search for ALL words Example: library AND academic OR  Will search for EITHER words Example: library OR academic NOT  Will eliminate words from being searched Example: library NOT academic

17. Phrase Searching Will find all words in a phrase next to each other Put “quotation marks” around the phrase  Example: “adolescent criminals” “Shakespeare in the park”

18. Keywords Keywords are words that the user puts in the search box to find results Can show up anywhere on the page Does not describe what the article/webpage is actually about

19. Subjects Words that actually describe what the article/webpage is about The author typically assigns subjects headings More specific to a topic  Think Subject Directory