In many information resources (catalogues, databases, bibliographies, the internet search engines) it is possible to combine search terms directly with logical operators, called Boolean Operators: AND, OR & NOT
The advantage of the use of Boolean Operators (Boolean searching) is that they allow the list of hits to be reduced to an acceptable and relevant number.
The results of searches in which search terms, or results of individual searches, are combined, can also be represented graphically.
Search techniques Boolean operators: AND, OR, NOT AND NOT OR
Suppose you are interested in literature on radioactive waste.
Possible search terms:
radioactive waste nuclear
radioactive waste = literature on ‘ waste’ ‘ radioactive’ ‘ radioactive waste’
Search result can be narrowed down to ‘radioactive waste’ by using AND . radioactive waste AND
Search terms or results of searches are combined with NOT if you want to exclude certain references. waste NOT spillage
radioactive nuclear Suppose you want to collect all literature on ‘radioactive‘, you need to use also its synonyms, e.g. ‘nuclear'.
Combining with OR , the resulting collection contains literature in which at least one of the search terms occurs. radioactive OR nuclear
( ) radioactive OR nuclear waste AND Example of creating a search query using Boolean Operators