Use NVCC Library s Best of the Web Determine whether you should use a subject directory or a search engine. Subject directories are created by people, and provide a collection of links to Internet sites organized into subject categories. They are usually more selective than search engines. Subject directories usually provide a search engine to query their holdings.
Search engines are computer-generated searchable databases of Internet resources.
They usually log each word on each web page, so when a search engine is queried, it will search for your terms on each page in its collection. Database content will not show up in a search engine result. This includes databases available through the library home page, such as Expanded Academic and the library catalog, as well as other online databases. These resources have been called the Invisible Web since the information in these databases cannot be seen by search engines. When you want to avoid getting pages that only mention your term once or twice.