1. An information retrieval method carried out by an information retrieval system including a meta search engine with a snippet engine having a database storing previously selected search results and a snippet index to the database, the snippet index having terms included in snippets of the selected search results when they were previously selected, a snippet being a query-based summary of a result document that is returned by an underlying search engine and containing extracts from the content of the result document related to the terms in the search query that produced the result document, wherein there are a plurality of snippet indices, and a particular snippet index is dynamically selected according to a community for the user; and at least one underlying search engine, the method comprising the steps of: the meta search engine receiving a user information query in the form of key terms; the meta search engine submitting the query to each underlying search engine; submitting the user information query to the snippet engine; the snippet engine retrieving results according to matching of the query terms with the snippet index; the meta search engine receiving results from each underlying search engine; and the meta search engine merging the underlying search engine results with the snippet engine results to provide output user results, and submitting the output user results to the user: monitoring which results of the output user results are selected by the user, and updating the snippet database and snippet index accordingly; indexing a selected result in the snippet index on the terms in the snippet returned by the underlying search engine; and weighing repeat terms in a snippet as they are used to modify the snippet index.
5. The information retrieval method as claimed in claim 1 , wherein the snippet engine ranks its results according to similarity of the query terms and the index terms.