What is meta search?
When performing a Web search a search engine will generally scan its own and sometimes one or two of its partners' listings. Thus, the search results, albeit comprehensive, for the most part stem from a limited number of sources and therefore, theoretically could miss certain important results listed with engines other than the ones employed by the particular engine. That is why meta search offers an alternative to Google, Yahoo!, MSN, and other heavily-used search engines. There is no guarantee that meta-search results are more comprehensive than those of regular search engines. But more sources will be queried, and there is thus at least a chance that utilizing a meta-search engine will provide results that would have been missed otherwise. Most meta-search engines include Google, LookSmart and other industry leaders, as well as a number of smaller engines in their queries.
The Nature of Meta Search
Meta search — offered by such engines as Dogpile, MetaCrawler, mamma, and ProFusion — means to simultaneously engage several search engines and have each of the source engines return its own list of results for a given keyword or phrase. Mostly, meta-search engines display the combined search results on one, prioritized list, which thus might mix listings from several sources. Others list each search engine's results separately. That way the user not only can tell exactly which results each individual engine returned, but also how each one ranked the results
Because meta-search engines generally rely entirely on other search engines' indices, it is usually not possible for Web site owners to submit their sites directly to a meta-search engine. Rather, in order to have a site listed with a meta-search engine, the site should be submitted to and secured an opportune ranking with one or more of the source engines used for the meta search. However, each of InfoSpace's meta-search engines — Dogpile, MetaCrawler and WebCrawler — enables users to submit Web sites to the paid-inclusion Search Partner Network. The Search Partner Network is queried as part of the meta search.