Boolean operators are ways of linking more than one keyword. They come
in three basic flavors: AND, OR, and NOT. When you use them, you can
limit or increase the number of titles you come up with, also known as
AND is a limiting operator. When you search for peanut AND butter, you'll find only those titles or Web sites that mention both "peanut" and "butter." You won't come up with peanut sauce, nor with almond butter, but you will find peanut butter and may find a recipe for peanut cookies made with butter.
OR is an expanding operator. If you search for peanut OR butter, you'll find everything that mentions peanuts and everything that mentions butter. If you're just looking for "peanut butter," this isn't a good way to do it. If you're looking for information about a topic that people refer to in more than one way, however, OR is a good choice. For example, you would want Cambodia OR Kampuchea if you were looking for information about that country.
NOT is a limiting operator. Searching for peanut NOT butter would eliminate references to peanut butter and to the peanut cookie recipe that uses butter. If you just wanted information about growing peanuts, it would be a good approach.
You can put more than one Boolean operator into the same search, though it's not wise to use too many at once.
1. List topics you might get with the following:
a) rainforest AND trees
b) rainforest NOT trees
c) rainforest OR trees
2. How would you search for information about rainforests that are outside the US?
3. What would you put to get information about family planning in China?
4. Which letters on
the diagram above show A and B and C?
Which show A or B?
Which letters are (A or B) not C?
Which show B and C?
Which show (B or C) not A?
1. Put the following terms in order from broadest to narrowest:
San Jose, Costa Rica
2. You're interested in the rainforest in Costa Rica, but you're not finding much. What synonyms could you use to make a broader search?
3. You want to find out about endangered species, but there's too much information. How will you narrow your search?
If you have questions, comments, or for more information, contact Deborah Healey, dhealey AT uoregon DOT edu
Last updated 26 June, 2009