Boolean search
A search for data that meets several criteria by using the Boolean operators AND, OR and NOT (see Boolean logic). For example, the request: "Search for all Spanish and French speaking employees who have MBAs" would be written as follows if the query were expressed on a command line. Spanish and French are placed in parentheses in order to be treated as a single item.
list for degree="MBA" and (language="Spanish" or language="French")
In the following example, the parentheses are missing, and the query is incorrect. The AND ties MBA and Spanish together; therefore, people who speak Spanish and have an MBA would be selected, which is correct. However, the OR separates French from the rest of the query, and anyone speaking French, no matter which degree they held, would also be selected.
list for degree="MBA" and language="Spanish" or language="French"
A Google "Advanced" (Boolean) Search
Searching text on Web pages is much less exact than querying records in a database, and this search actually produced 10 million results. However, the Boolean concept does still apply. In this Google "Advanced Search," the OR is stated clearly, but the AND and NOT operators are there nonetheless.