BOOLEAN OPERATORS Presented by Nancy Law, Media Specialist Columbiana Middle School

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.com

www.google.com

Using Boolean operators,

Which search term retrieved the most hits?

Which terms narrowed your search?