While the quantity of information available over the Internet is extensive, the quality of that information varies considerably. It is important to know what types of resources are available on the Internet and what types are not. Typically, resources such as magazine and journal articles are not freely available to the general researcher. For research papers, controlled databases available in the library such as MasterFile and Britannica will yield considerably better results. Finally, it is important to evaluate any information taken from an Internet source since virtually anyone, regardless of their background and knowledge, can create and post documents to the Web.
A simple and powerful searching technique for locating Internet resources utilizes the plus and minus (-) signs which are known as implied Boolean operators.
When searching, if a plus sign (+) is placed directly in front of a word it will force the search engine to return only those documents that have that specific word. Example: +"global warming" +environment +science
If a minus sign (-) is placed directly in front of a search word, it will tell the search engine NOT to return any documents containing that particular word. Example: +pollution +water -air
When searching for phrases, place the words in quotation marks as shown in the first example.