Answer:
Search engine usually have their own database of sites they craw and list in their database, for example Google, Yahoo, Ask.
Meta Search Engines usually do not have their own database of crawled sites, they search the databases of real search engines, usually many search engines at the same time, and provide you results. So a meta search engine will give you results from say Yahoo and Google, some meta search engines do have database of sites submitted to them. Example of a meta search engine is DogPile.