INTERNET ESSENTIALS Search Engines and Searching the Web

What you will learn Search Engine Basics Formulating Searches The Web and 2

Search Engine Basics A Web search engine is a program designed to help locate information on the Web by formulating simple keyword queries.

Search Engines A search engine is helpful in locating information for which you may not know the exact web address on web pages on various topics locating specific web pages images videos There are thousands of search engines available.

Search Engines & Types GoogleSearch engine LycosDirectory Alta VistaSearch engine YahooDirectory BingSearch engine MSNDirectory AOLDirectory HotBotSearch engine

The Different Types of Search Engines The term "search engine" is often used indiscriminately to describe: Web crawler “search engines” human-powered “directories” Hybrids - uses both

Web Crawler Crawler-based search engines such as Google, compile their listings automatically They "crawl" or "spider" the web, and people search through their listings Spiders scour the web on a regular basis. Listings are what make up the search engine's index or catalog The index can be defined as a massive electronic filing cabinet containing copies of every web page the spider finds

Directories Directories depend on human editors to compile their listings Webmasters submit an address, title, and a brief description of their site, and the submission is reviewed After a web site makes it into a directory it is generally very difficult to change its search engine ranking

Hybrid search engines Some search engines offer both crawler-based results and human compiled listings called “hybrid search engines”. They typically favor one type of listing. AOL usually displays human-powered listings. But uses Google as a secondary engine.

Search Engine Basics Search engines require you to enter a word or phase, “search text” or “keyword” that describe the item you want to find They often respond with results that include thousands of results, whose content varies based on the information you are seeking.

Activity Let test several search engines to see if we can determine if it’s a directory or web crawler. Have a couple students go the following search engines: Bing, yahoo, google and aol Have the student search for a specific item (i.e. Dr.J ABA) Record the results from each search engine and the discuss the result Which do you think is a directory verses web crawler? When would you want to use a web crawler vs a directory?

Formulating Searches Most search engines are not case sensitive (Shift key usage not necessary) Search engines ignore common words like: (and, a, & the) there is no need for them. To search for an exact phrase, enter it in quotation marks. The asterisk (*) is referred to as the wildcard charter. *ball = baseball, football, basketball, volleyball

13 Boolean Search A Boolean operator is a word or symbol that describes a relationship between keywords, Helps you create a more focused query AND (+) - If words are joined by AND both words must appear on a web page before it can be included in the results. OR – If two words are joined by OR then either word or both words could appear on a page. NOT (-) – A keyword following a NOT must not appear on any of the pages found by the search. Example poverty and crime, poverty orcrime, poverty not crime

Boolean Reference Guide PhraseBoolean Logic Exact Phrase“Boolean Logic” AndBoolean AND Logic +Boolean +Logic OrBoolean OR Logic Boolean Logic NotBoolean AND NOT Logic +Boolean –NOT Logic Truncation/Wild CardBoo*

Activity Record the number of hits and compare the results. Search for: SearchHits Water Pollution +water +pollution cowboys cowboys -football cowboys versus 49ers "cowboys versus 49ers"

Activity: Internet search Practice Directions: try to answer the following questions using an internet search engine. 1. Who is the governor of North Carolina? 2. Who is the president of Brazil? 3. What is the capital of China? 4. What is the approximate population of California? 5. Who won the American league baseball world series in 1998? 6. How fast can a cheetah run? 7. How old was George Washington when he died?