Boolean Combinations
Boolean operators--OR, AND, NOT--are used between search terms to combine concepts in a more precise way than is possible with keyword searching.
| AND | |
Image  | The AND operator narrows a search, retrieving only records containing both term(s). AND is used to narrow a topic to a specific aspect. Example: anorexia AND "college students" |
| OR | |
Image  | The OR operator broadens a search, retrieving records that contain either term, but not necessarily both. It is used to combine synonyms or related concepts. Example: anorexia OR bulimia |
| NOT | |
Image  | The NOT operator also narrows a search by removing all records that contain a particular word or phrase. Example: anorexia NOT bulimia The NOT operator is rarely used. It often screens out useful records. |
