Use the terms “AND,” “OR” and “NOT” to narrow a search and include or exclude some of the results of a search. By using these logic terms in conjunction with your topic search, you can find niches of information on a subject without having to search through information that is beyond your interest.

## How Boolean Logic Works

The “AND,” “NOT” and “OR” operators are normally applied to grouping theory and algebra. By using the operators in the correct manner, you can isolate single or small groups of items in a relatively quick manner. In terms of Internet searches, the database you have to work with has millions of entries that examine topics in a variety of subject areas, so this can be especially valuable.

To use the Boolean operators, you must begin by defining your general subject by performing a general search on the database for everything that concerns your topic. To maximize your efforts, you can then use the Boolean operators to exclude all the types of information that you aren’t interested in. By excluding the areas and minor topics from the general responses, you will decrease the number of entries that will have to be examined one-by-one.

A good way to understand the Boolean process and learn how to apply Boolean logic is to look at a few examples. The process of using Boolean logic begins in a general manner and then you narrow the results, much like the child’s game of 20 Questions. Here's the process:

- Define the information that you seek. Assume, for example, you are interested in finding information on the mating habits of African elephants. You would begin your search of the database by searching “elephants.” This will yield a large number of entries (set 1.)

- To narrow your search to include only those entries that are about African elephants, search “elephants AND African.” Now the answer (set, 2,) contains results that deal only with African Elephants.

- Refine the search results further by searching that set of results (set 2) for entries on mating by typing “answer set 2 AND mating.” The answer to that search should yield the smallest set of entries that you must go through to find your information.

- There are other searching schemes that may reduce your answer set further or allow you to search quicker, but those are based on what the order the search is to be performed in.

- If the last search terms were typed as “answer set 2 AND mating OR reproduction” the set of articles in the answer set would be different. You must apply the train of logic to the searching process.

A computer can perform the process of searching and classifying in much less time than a human would take. It only has to decide between yes and no on a particular word or term. By designing a set of yes and no search questions, you will logically find what you are looking for. The time consuming aspects of finding information will be in designing the strategy for weeding out the nonessential information from the bulk of the information available.

## Boolean

Origin of Boolean

after G.*Boole*(1815-64), Eng mathematician

## Boolean

adjective

- Of or relating to a logical combinatorial system treating variables, such as propositions and computer logic elements, through the operators AND, OR, NOT, and XOR:
*a browser that supports Boolean searches.* - Of or relating to a data type or variable in a programming language that can have one of two values, true or false.

Origin of Boolean

After George**Boole**.

## boolean

(*not comparable*)

- Alternative capitalization of
*Boolean*.

(*plural* booleans)

- Alternative capitalization of
*Boolean*.

## boolean - Computer Definition

See Boolean logic.