Logical operators, also called Boolean operators, serve to help you search synonyms together as well as separate different concepts.
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OR |
Expands your search. Use with synonyms, such as those you listed above. Any of the terms will be in the record. |
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AND |
Narrows your search. Use with different concepts. All search terms must be in the record. |
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NOT |
Eliminates results. Use this selectively. It is often better to add more terms or use limits to narrow your search |
The star * is the truncation symbol for most library databases.
Use it to find all words that start with those letters.
Truncation functions much like a Boolean "OR," as described above.
Histor* finds history, histories, historical, historians, etc.
A search for history* finds only history.
Most library databases assign subjects terms to help with searching. It is important to discover what they call what you want to find, so you can search on their terms.
For example, if you were looking for information about African Americans, you would use different subject headings depending upon the database.
Database:
Concepts | Subject Descriptors | ||
1 | |||
2 | |||
3 |
Database:
Concepts | Subject Descriptors | ||
1 | |||
2 | |||
3 |
Database:
Concepts | Subject Descriptors | ||
1 | |||
2 | |||
3 |
Not all publishers should be trusted equally. When searching the library catalog or WorldCat, limit to "university" as the publisher. This is not perfect, there are excellent non-academic publishers and poorly researched books produced by some universities; yet, it can be helpful.