What is Boolean logic?
Boolean logic is a mathematics-based system for performing logical operations. A logical operation is way of defining the relationship between two or more things.
Boolean logic is part of an algebraic system developed in the mid 1800s by a British mathematician and philosopher named George Boole. Boole demonstrated that powerful complex mathematical operations could be performed by using simple binary terms connected by the operators: AND, OR, NOT.
Both Boolean algebra and Boolean logic are binary systems. In a binary system, only two values are present. Something can be on or off. Something can be true or false. Something can be yes or no. Something can be 0 or 1. In a binary system, there are no greys; everything is black or white.
After Boole's death, people leaned that electrical signals could easily and reliably act as a binary system too. Signals could have two values: low current or high current. This meant that complex Boolean algebraic operations to be performed electronically. And so it was that Boolean logic became the foundation of computer science and the bases of the digital hardware and software technologies we have today, including Internet search engines.
Almost all modern search engines are based on Boolean logic, and use the Boolean operators AND, OR, and NOT.
A search engine is the set of underlying rules that perform a search. The same search engine might appear in many different places, with a different interface or look and feel on top of it, much as the same engine might appear in several different varieties of cars. Google and Bing are two of the commonly incorporated search engines.
The Glean tool Boolify helps you better understand and therefore better perform Internet searches. Boolify uses Microsoft’s Bing search engine. Even though every search engine is based on Boolean logic, each has its own quirks and variations, so be aware that Boolify will also illustrate Bing’s search methodology.
Using Boolify:
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Basic Search Operations: Keywords This short video introduces basic search concepts, including how to add keywords and phrases to the Boolify engine. |
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Basic Search Operations: Saving Searches and Changing Options This short video demonstrates saving searches, and indicates how results can be explored across web, news and image results sets. |
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Intermediate Search Operations: Using OR and NOT in Searches This short video demonstrates how to use OR and NOT to refine and limit search results. |
More About Boolean:
You can view information about George Boole, the inventor of Boolean, on Wikipeidia, or read his book at Project Gutenburg.
