Presentation on theme: "BOOLEAN OPERATORS Presented by Nancy Law, Media Specialist Columbiana Middle School."— Presentation transcript:
BOOLEAN OPERATORS Presented by Nancy Law, Media Specialist Columbiana Middle School
What are Boolean Operators? AND OR NOT Tell search engines which keywords to include or exclude CAPITALIZE BOOLEAN OPERATORS
Named after George Boole, an Englishman, who invented them as part of a system of logic in the mid-1800’s.
AND Gives “fewer” hits Example: ocean AND fish Means the same as + oceans + fish Each of these search statements will find documents containing both terms, oceans and fish.
EXAMPLE: Oceans AND fish AND
Gives more “Hits” OR Example: fish or oceans Both of these words will appear in search documents.
Gives fewer “Hits” NOT -sign means the same as NOT Example: ocean NOT fish +ocean-fish Both of the above statements will retrieve documents containing ocean but not containing the term fish.
If you are retrieving too many records on your topic: add another search term with the connector AND. Example: Poverty AND Crime- Limits search to hits that contain both words
If you are retrieving too many records on an unrelated topic: eliminate a word with the connector NOT. Saturn NOT Car – (Limits – returns first keyword, not second
If you are retrieving too few records on your topic: add another search term with the connector OR. Example: College OR University- Expands search
PRACTICE Imagine your teacher has assigned a research report on Ruth Handler and the invention of the Barbie Doll. Write some keywords you would use to search the Web for this topic. Be sure to use Boolean operators that will make your results more specific. Examples: Inventions, Ruth Handler, Barbie Doll, Ruth Handler AND Barbie Doll, Ruth Handler OR Barbie Doll, Barbie Doll AND Ruth Handler, Barbie Doll NOT clothes, Invention and Barbie Doll
Use each of the following search engines to find web pages related to your topic: www.Yahoo.com. www.Google.com. www.Lycos.com.ww.google.comww.google.com www.google.com
Using Boolean operators, Which search term retrieved the most hits? Which terms narrowed your search?