Keywords are terms that describe the topic you are researching. Keywords can be a people, places, things, ideas, or concepts. We need keywords to effectively search in library academic databases (like CLIO or Jstor). Unlike internet browsers, which have developed to understand full questions written in natural language, academic databases use keywords to locate resources.
There are no perfect searches when using keywords, which is why it's useful to brainstorm lots of related terms and/or synonyms to locate what you are looking for. For example, we might use the word "teenager" to describe a particular population, but the term "youth" might be used in a database instead. You can also find new keywords once you begin searching in the content section and subject sections of a catalog entry.
Boolean searching is based on an algebraic system of logic formulated by George Boole, a 19th century English mathematician.
In a Boolean keyword search, the terms are combined by the operators AND, OR and NOT (in upper case) to narrow or broaden the search (in CLIO, Ovid, and some other databases, you DO have to enter them in capitals). This type of search is possible in most library catalogs and databases, but Google and other Web search engines do not carry out OR and NOT searches properly.
These Venn diagrams help to visualize the meaning of AND, OR and NOT; the colored area indicates the items that will be retrieved in each case.
The operator AND narrows the search by instructing the search engine to search for all the records containing the first keyword, then for all the records containing the second keyword, and show only those records that contain both.
Sample Search: Feminism AND Postmodernism
The operator OR broadens the search to include records containing either keyword, or both. The OR search is particularly useful when there are several common synonyms for a concept, or variant spellings of a word.
Sample Search: Adolescents OR Teens
Combining search terms with the NOT operator narrows the search by excluding unwanted terms.
Sample Search: "Star Wars" NOT Film
Quotation marks allow you to search terms as a phrase. This narrows your search by excluding results that may contain the same words, but not in the specific arrangement within the quotation marks.
Sample Search: "Barnard College"
The asterisk allows you to search portions of words to enable searching multiple similar words at the same time.
Sample Search: Feminis* searches Feminist, Feminists, Feminism and Feminisms
Parenthesis allow you to create long search strings with OR statements so you can apply a term relationship to multiple words at once time.
Sample Search: Puritans AND (Rhode Island OR New Hampshire OR Massachusetts)