Engines

Search engines are computer programs that search the internet looking for specific information. They should be used when you have a definite topic in mind. They usually allow the user to do "Boolean" searches.

Meta-Search Engines

Meta-search engines are powerful computer programs that search many other search engines. They should be used to locate information about topics which have been proven to be very difficult to find. They are much more thorough than regular search engines and result in many more hits, which is frequently a disadvantage.