Sets of keywords and symbols that refine internet search requests are called boolean operators microsoft operators apple operators english operators

Boolean operators, it uses the word "and","or" and "not" with keywords to control the search. For example if you search for health and food, the search engine will give a narrow search focusing on the two keywords. Using "or" with keywords will give much broader results. Using a "not" will remove one keyword from the search, ex. windy not rainy will give results of the keyword windy only. An asterisk on the other hand, gives wider results with variations.