Search Engine Ankush Srivastava Search Engine MCA VI Semester Dept. of Computer Science University of Lucknow Lucknow.
Searching What is searching and what we search? Search Engine Somewhere in a collection of documents, Web pages, and other sources, there is information that we want to find, but we have no idea where it is. The searching process give us the means of finding that information.
System Based Searching Search Engine Its complete indexing of all the files in the computer like documents, texts, music, pictures etc. The program allows text searches of a users needed files. For Example Google Desktop.
Web Based Searching A web based searching is designed to search information on the internet or World Wide Web. Search Engine For Example Google, Yahoo etc.
Crawler-Based Crawler-based search engines use automated software programs to survey and categories web pages. The programs used by the search engines to access your web pages are called ‘spiders’, ‘crawlers’, ‘robots’ or ‘bots’. A spider will find a web page, download it and analyses the Search Engine information presented on the web page. This is a seamless process. The web page will then be added to the search engine’s database. Crawler-based search engines are constantly searching the Internet for new web pages and updating their database of information with these new or altered pages. Eg:- Google
DirectoriesA ‘directory’ uses human editors who decide what category the sitebelongs to; they place websites within specific categories in the‘directories’ database. The human editors comprehensively check thewebsite and rank it, based on the information they find, using a pre-defined set of rules. Search EngineFor eg:Yahoo Directory (www.yahoo.com )Open Directory (www.dmoz.org )
Hybrid SearchEngines Hybrid search engines use a combination of both crawler-based results and directory results. More and more search engines these Search Engine days are moving to a hybrid-based model. Examples of hybrid search engines are: Yahoo (www.yahoo.com ) Google (www.google.com )
Meta Search Engines Meta search engines take the results from all the other search engines results, and combine them into one large listing. Examples of Meta search engines include: Search Engine Metacrawler (www.metacrawler.com ) Dogpile (www.dogpile.com )
Paid InclusionMost directories offer some form of paid inclusion. Paid inclusion Search Engineguarantees your website gets reviewed and/or indexed promptly.
Specialty SearchEngines Specialty search engines have been developed to cater for the demands of niche areas. There are many specialty search engines, including: Search Engine Shopping - Froogle (www.froogle.com ) - Yahoo Shopping (www.shopping.yahoo.com ) Local Search - NZPages (www.nzpages.co.nz ) - SearchNZ (www.searchnz.co.nz )