1. SEARCH ENGINE by: by: B.Anudeep B.Anudeep Y5CS016 Y5CS016

2. What is a Search Engine? ● A page on the web connected to a backend program Allows a user to enter words which characterise a required page Allows a user to enter words which characterise a required page Returns links to pages which match the query Returns links to pages which match the query

3. HISTORY OF SEARCH ENGINE Almost 20 years after the creation of the Internet, the World Wide Web was born to allow the public exchange of information on a global basis. It was built on the backbone of the Internet Almost 20 years after the creation of the Internet, the World Wide Web was born to allow the public exchange of information on a global basis. It was built on the backbone of the Internet The very first tool used for searching on the Internet was called "Archie". The very first tool used for searching on the Internet was called "Archie". While Archie indexed computer files, "Gopher" indexed plain text documents While Archie indexed computer files, "Gopher" indexed plain text documents Because these were text files, most of the Gopher sites became Web sites after the creation of the World Wide Web. Because these were text files, most of the Gopher sites became Web sites after the creation of the World Wide Web.

4. Components of a Search Engine Robot (or Worm or Spider) Robot (or Worm or Spider) collects pages collects pages checks for page changes checks for page changes Indexer Indexer constructs a sophisticated file structure to enable fast page retrieval constructs a sophisticated file structure to enable fast page retrieval Searcher Searcher satisfies user queries satisfies user queries

5. Types of Search Engine Automatic search engine e.g. AltaVista, Lycos Automatic search engine e.g. AltaVista, Lycos Classified Directory e.g. Yahoo! Classified Directory e.g. Yahoo! Meta-Search Engine e.g. Dog pile Meta-Search Engine e.g. Dog pile

6. LIST OF SEARCH ENGINES EXCITE (1993) EXCITE (1993) YAHOO,WEBCRAWLER,LYCOS(1994) YAHOO,WEBCRAWLER,LYCOS(1994) INFOSEEK,ALTAVISTA(1995) INFOSEEK,ALTAVISTA(1995) INKTOMI(1996) INKTOMI(1996) GOOGLE(1997) GOOGLE(1997) MSN SEARCH(1998) MSN SEARCH(1998)

7. Who operates Search Engines? People who can get money from venture capitalists! People who can get money from venture capitalists! Many search engines originate from U.S. universities Many search engines originate from U.S. universities Often paid for by advertisements Often paid for by advertisements Engines monitor carefully what else interests you (paid by the click) Engines monitor carefully what else interests you (paid by the click)

8. How do pages get into a Search Engine? Robot discovery (following links) Robot discovery (following links) Self submission Self submission PAYMENTS PAYMENTS

9. HOW TO ACESS ? Create an Index Create an Index Receive a query -- a set of search terms and commands Receive a query -- a set of search terms and commands Look in the index file for matches Look in the index file for matches Gather the matching page entries and rank them by relevance Gather the matching page entries and rank them by relevance Format the results Format the results Return the result page in HTML to the searcher’s web browser Return the result page in HTML to the searcher’s web browser

10. indexer query Format result Data base Search the crawler processor

11. A Typical Search Engine

12. conclusion Search Engines are vital to the Web user Search Engines are vital to the Web user Search Engines are not perfect by a long way Search Engines are not perfect by a long way There are tactics for better searching There are tactics for better searching Page design can bring more visitors via Search Engines Page design can bring more visitors via Search Engines The more links the better! The more links the better!