WebJunction

There are two major ways to write a search request that will refine your search and provide more focused results, if the search engine allows such techniques. You and your patrons already may have encountered searching syntax systems called "symbols" (also known as "implied Boolean operators" and "Boolean operators." Both are popular -- and similar -- methods of narrowing down Internet searches.

Symbols (also called "Implied Boolean operators")

+ The plus symbol ensures that a term is entered in the search. For example, if you want your search to reveal recipes for strawberry shortcake, you could write +strawberry+shortcake+recipes. Only pages that included all three words would appear in your search.

- The minus symbol allows you to limit a search. If you wanted articles on strawberry shortcake, but you wanted to exclude recipes, you could write +strawberry+shortcake-recipes.

The + and - symbols are especially helpful when you do a search and then find yourself overwhelmed with information.

" " Quotation marks act as another limiting function for your search. For example, if you were to find that strawberry shortcake recipes also included hits on the cartoon character "Strawberry Shortcake" and her favorite recipes, you would need to use quotation marks. "Strawberry Shortcake Recipes" in quotes would tell the search engine to find the words next to each other. This is also called phrase searching.

* Using a wildcard or asterisk (*) is useful if you don't have a complete spelling. For instance, ambidex* would get you much closer to finding out about the faculty of being nimble with both hands than the misspelled word (ambidexterous is the way it is commonly misspelled). It's also useful if you don't remember the exact term you're looking for, as in micro*. This will yield hits on microbreweries as well as the microprocessors that were intended to be the topic searched, but it gets the user closer to the desired subject. The asterisk is also useful in hitting more than one form of the word. For example, Cancer* will hit cancerous, cancer, and cancers.

Boolean operators

Boolean operator is a term that refers to a system of logic developed by British mathematician George Boole (1815-64). Boolean operators work in the same way that the plus and minus symbols work. The Boolean Operators are: AND, NOT, and OR. They are written in all capital letters so the search engine will not include them in the search. This search will look for Web sites that contain any of those key terms. Citizenship AND naturalization will yield a much more focused search for sites that contain both those key words. In other words, the connector AND makes for narrow queries, and the connector OR widens queries a bit. Some but not all search engines allow you to use Boolean operators.

Looksmart and Google do not allow for limitations on searching like AND or NOT due to the functionality of these sites.

Alta Vista's advanced search, HotBot, and Excite do allow Boolean operators.

Resources on Boolean logic

Albany University's Boolean Tutorial has a famous chart that is the universal model for Boolean Operators. It also has a chart listing which search engines allow Boolean Operators and which do not.

Search Engine Watch has a good summary on keyword searching and search commands.