To access a search engine go to the search engine s web site (i.e. yahoo.com).

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1 L02. Internet Search Page 1 of 6 L02. INTERNET SEARCH OBJECTIVES Students will be able to: Describe what a web search engine does. Describe how a web search engine works. Develop search strategies to effectively use web search tools to find information by: o Determining desired results. o Selecting the best search tool to obtain those results. o Selecting and finding key words. o Creating a search query using basic and advanced search techniques. o Analyze search results and refine search queries. REVIEW: WHAT IS THE WORLD WIDE WEB? The World Wide Web, or Web, refers to the billions of documents designed to be downloaded via the Internet and viewed by a special program called a web browser. Web documents contain hyperlinks that allow readers to jump from one document to another with a click of the mouse. Hyperlinks can also be gateways to audio and video broadcasts, animations, and other types of media. WHAT IS A SEARCH ENGINE? A search engine is collection of software designed to collect words from web pages, rank and index the words, and create a database that can be searched. This means that when using a search engine, you are not actually searching the Web; you are searching the database that has been created. To access a search engine go to the search engine s web site (i.e. yahoo.com). HOW DOES A SEARCH ENGINE WORK? A search engine makes use of small programs called robots, spiders, or crawlers that visit web pages and collect the words and hyperlinks that it finds. This process is called crawling. Different search engines have their crawlers use different strategies for collecting words. For example, some crawlers collect only the first twenty or fifty words on a page, some crawlers may ignore common words like a and the, and some may collect every single word on a page. The crawler gives its collection of words to the search database for ranking and indexing while the crawler continues its journey by following the hyperlinks it found. So the crawler never really stops crawling. It is constantly following links and reporting back to the search engine with the words it collects. Once the search engine has a list of words, it uses meta-information to rank and index those words. Meta-information includes things like the number of times a

2 L02. Internet Search Page 2 of 6 word appears on a page, a word s location on a page, and other more sophisticated bits of data. Based on analysis of this meta-information, the search engine then assigns a rank to the words. Finally, it sorts the words and their rankings to make them easier to find. As you might expect, different search engines use different methods of ranking and sorting which is why results may vary from one search engine to the next. TYPES OF SEARCH ENGINES Subject Directories: A categorical listing of topics with links to individual web sites. Directories are usually created with the help of human editors as opposed to robots or crawlers. Editors rate and rank the sites to be included in the directory. Subject directories are good for narrowing down a topic or browsing a large list of topics. Examples include: Yahoo! Directory (dir.yahoo.com) and Open Directory (dmoz.org). Individual Search Engines: Create and maintain their own database of indexed and ranked words for searching. Use individual search engines if you are looking for specific information about a topic. Examples Include: Google (google.com) and Yahoo! Search (yahoo.com. Metasearchers: These search engines do not create a database of their own. Instead, they search multiple individual search engines and present the results in one convenient list. Metasearchers are a good way to get a feel for how much information is available for a specific topic. Examples include Dogpile (dogpile.com) and Mamma (mamma.com). SEARCH STRATEGY KICKOFF Developing a search strategy begins with determining what your needs are: What are you looking for? Type of search Examples Broad range of topics in a specific category Subject Directory Astronomy Football A lot of information about a specific topic. Specific facts Meta-search engine Individual Search Engine Aurora Borealis (Northern Lights) Indianapolis Colts Aurora Borealis particle speed Peyton Manning s passing statistics

3 L02. Internet Search Page 3 of 6 BASIC SEARCH TECHNIQUES Be specific: Use words that clarify what you are interested in finding. blizzard 1978 (instead of: blizzard ) hurricane andrew (instead of: hurricane or andrew ) Put words in the order you would normally expect them to appear. dog show (gives results about dog shows, kennel clubs, etc ) show dog (gives results about raising, grooming, or handling dogs) Avoid using common words unless they are part of a phrase. weather patterns rain forest (instead of: weather patterns in the rain forest) Consider synonyms or other words you would expect to find in a document about the topic. effects of media OR TV OR video game violence teenagers OR adolescents. (Instead of: effects of media violence on teens) Use search focus options: Many search engines allow you to perform media specific searches. For example, Google allows you to search for specific elements such as images, videos, News stories, blogs, maps, newsgroups, etc ADVANCED SEARCH TECHNIQUES Boolean logic (AND, OR, NOT): Most search engines allow you to add these words to your query to narrow or broaden your search: Boolean AND: Results list will include documents that have all of the keywords you enter with an AND between them. This will narrow your search. The more keywords you link with AND, the narrower your search becomes. nascar AND daytona AND crash AND roll Boolean OR: Results list will include documents that have any or all of the keywords you enter with OR between them. This will broaden your search. The more keywords you link with OR, the broader your search becomes. The OR term is useful when keywords have synonyms. stress OR anxiety

4 L02. Internet Search Page 4 of 6 Boolean NOT or AND NOT: The NOT or AND NOT term allows you exclude documents containing the keywords with NOT in front of them. This will narrow your search. To find out which term to use, you will have to use the help link of the search engine. diabetes AND obesity AND NOT pregnancy Implied Boolean operators (+, -): the plus (+) and minus (-) signs can be used in place of the Boolean AND and Boolean NOT. zeppelin led (returns documents about the zeppelin aircraft but not the rock band Led Zeppelin) Phrase searching ( ): placing quotes around a phrase forces the search engine to only include documents where the words inside the quotes appear as a phrase (side by side) in the document. Star Wars episode I or You re gonna need a bigger boat" Wildcards (*): If you want the search to include plurals, alternative endings, or alternative spellings, try using wildcards (not all search engines accept these). comput* (returns computer, computing, computers, computation) fav*rite (returns American & British spellings favorite and favourite) Advanced search form: Many web search engines have a form you can use to perform advanced searches. On these forms you may find several phrases that correlate with the terms discussed above. Some of those are: o With all the words: Same as entering all keywords using the AND or plus (+) operator. o With at least one of the words: Same as entering all keywords using the OR operator. o With the exact phrase: Same as using quotes around a group of words. o Without the words: Same as using the NOT or minus (-) operator

5 L02. Internet Search Page 5 of 6 ANALYZING RESULTS No matter how much you plan your search, you will still occasionally run into a situation where you just can t seem to find what you are looking for. Here are some tips for analyzing the results and refining your search. You will refine your search by finding new keywords and using advanced search techniques to filter out unwanted material, or to narrow or broaden your search. Usually the most relevant results will be on the first page, but if they are not, scan through the first five to ten pages of results. If you find something closer to what you are looking for, follow those links and look for new keywords. Consult a dictionary or thesaurus for synonyms. Recognize unwanted words and use the NOT or minus (-) operator to remove those documents from the search results. Broaden your search by using less keywords or less specific keywords. Narrow your search by using more keywords or more specific keywords. ODD AND ENDS There are many pages on the web that search engines ignore. For example, pages that are dynamic (created on demand) such as a request for account information, or pages that require registration or a login (like the Wor-Wic research databases). Since web pages are constantly changing, the search engine s database may not always be up-to-date. So sometimes the results may have links that no longer work or pages that no longer contain information related to your search. Individual web sites often include a search feature that allows you to search within the site. For example, go to Wor-Wic s home page and you will see the following in the upper right hand corner: Individual words or phrases can be found on a page by using the Edit > Find on this Page command on the menu or in IE 7 by clicking the Search list arrow > Find on this Page.

6 L02. Internet Search Page 6 of 6 PRACTICE #1 Decide which type of search (Subject Directory, Phrase Search, Keyword Search, or Wildcard Search) would be best for finding information on each topic listed below. Support your decision by writing an example or description of a search. For example, if the item listed was A topic for a history class paper, you might answer Subject Directory would be the best search to help narrow down a topic because it would provide a list of categories related to History. 1. Tips for conserving water (could also refer to water conservation) 2. Philosophical schools of thought 3. Treatments for a bee sting 4. A specific article (you have the title of the article) 5. Ideas for a fun weekend 6. Information on Internet search techniques PRACTICE #2 Underline the key words in the question then perform a search of the Internet to find the answers. Something to consider: Are you confident the web pages are giving you accurate information? 1. According to legend, an acorn kept on your window sill will supposedly keep your house safe from what? 2. In what U.S. museum can you view human medical anomalies? 3. In which stock exchange is the FTSE 100 index used to measure stock market performance? 4. When did Dr. Seuss win the Pulitzer Prize? 5. In Mark Twain wrote several letters to the Keokuk Post in Iowa. What name did he sign on those letters? 6. What country had the largest recorded earthquake?