There are three types of Boolean operators recognized by Google. They are the OR, AND and NOT operators.
The OR operator
The OR operator is used to include either one search term or the other in a query. The syntax is 'OR' or '' (pipe symbol). Try this as example: 'fame fortune' and 'fame OR fortune'.
The AND operator
The AND operator is used to include more than one search term in a single query. The syntax is 'AND' or ' ' (space). By default, Google includes all search terms submitted. Therefore, submitting 'hotel AND cheap AND good' is almost the same as submitting 'hotel cheap good'. Try it. Notice there's a slight difference in the search results. The search terms are grouped more closely without the AND operator and vice-versa.
The NOT operator
The extermely useful NOT operator is used to exclude search terms in the results. The syntax is '-' (minus sign) followed immediately by the search term to exclude. Here's an example: 'windows' and 'windows -microsoft'.
Google queries are not case-sensitive, with the exception of the OR and AND operators. Google recognizes 'OR' as the OR operator, and 'or', 'oR' and 'Or' as a search term, i.e. the word 'or'. Google will display very different results for 'tiger OR rabbit' and 'tiger or rabbit'. Try it.
Notice something missing in the 'tiger or rabbit' search results? Most likely, the 'or' search term is missing. Google ignores very common words. What if, under certain circumstances, you would like to include 'or' as a search term?
Notice something missing in the 'tiger or rabbit' search results? Most likely, the 'or' search term is missing. Google ignores very common words. What if, under certain circumstances, you would like to include 'or' as a search term?
Use the + operator or double quotes - read more here: Inclusion and Phrase.
