Boolean Operators for Search Engines  Search Engine Guides / Tutorials   |   How Search Engines Work SOME BOOLEAN OPERATORS Boolean operators are used to search many databases, incl. libraries,  not only Web-based indexes/directories. KEYWORD METHOD AND Finds only documents containing all of the specified words or phrases. "Computers AND viruses" finds documents with both the word computers and the word viruses. OR Finds documents containing at least one of the specified words or phrases. "Computers OR viruses" finds documents containing either computers or viruses.  The documents found could contain both, but do not have to. NEAR Finds documents containing both specified words or phrases positioned a certain number of words apart (assigned by the search engine).  NOT  Finds only documents which exclude the term after the word "NOT." "Computers NOT viruses" finds documents with the word "computers" but not the word "viruses." Search  Symbols METHOD + Terms preceeded with "+" indicate they have priority in the search. " " Phrases between quotation marks are search exactly as they are written.  * This symbol is used for Wildcard searching. For example, comput* will search Computer, computing, etc.   Search engine guides and tutorials: CNET search engine shoot-out - Guide to Metasearchers http://home.cnet.com/category/topic/0,10000,0-3817-7-276933,00.html PC Magazine Online: Your Complete Guide to Searching the Net (http://www.zdnet.com/pcmag/features/websearch/_open.htm) The Spider's Apprentice (http://www.monash.com/spidap3.html) Search Engine Watch (http://www.searchenginewatch.com/webmasters/index.html)   (Re)Search Desk: Search Engine Tutorials  (http://www.sar.bolton.ac.uk/Psych/main/RDesk/tutorials.htm)