Search

Search engines are information retrieval tools designed to find information stored on computer devices or networks. They can dramatically reduce the time required to find information. Search engines provide an interface that enables users to submit a search query. In the case of text search engines, the search query is typically expressed as a set of words. There are several styles of search query syntax. Some text search engines prompt users to enter two or three words separated by white space, other search engines enable users to specify entire documents, pictures, sounds, and various forms of natural language. To speed up the search process, search engines typically collect metadata about items of interest beforehand, through indexing. Some search engines do not store an index. Crawler, or spider type search engines collect and assess items at the time of search. Meta search engines reuse the index or results of other search engines. Text-based search engine technology is now quite mature. Most new technology development is focused on image-based search, in particular using semantic technology.