2. By, Rajanagan R Web Analyst Search Engines

4. History of Search Engines 1993: First web robot – World Wide Web Wanderer Matthew Gray, Physics student from MIT Objective: Track all pages on web to monitor growth of the web 1994: First search engine – WebCrawler, Brian Pinkerton, CS student from U of Washington Objective: Download web pages, store the links linked to keyword-searchable DB 1994: Jerry’s Guide to the Internet Jerry Yang, David Filo, Stanford University Objective: Crawl for web pages, organize them by content into hierarchies  Y et A nother H ierarchical O fficious O racle (Yahoo) 1994-97: Infoseek, AltaVista, Excite, Lycos, LookSmart (meta engine) Ranking Based on Content & Structure 1998: Google (Sergey Brin, Larry Page, CS students, Stanford University) Ranking Based on Content, Structure & Value 1990: First tool for Searching on Internet - Archie Alan Emtage, Student from McGill University in Montreal Objective: Tool for Indexing FTP archives, allowing people to find specific files.

5. How Search Engine Works..????

6. Step 1: Crawling Want to See what Crawler looks @ Click Here

7. Crawler Looks @ Example

8. Back This is what I look in a website..!!!

9. Step 2 : Indexing

10. Indexed Database Click Here

11. Back

12. Step 3 : Processing Query

13. Step 4 : Ranking

14. Overall Functioning of Search Engines Your Browser The Web URL1 URL2 URL3 URL4 Crawler Indexer Search Engine Database Eggs? Eggs. Eggs - 90% Eggo - 81% Ego- 40% Huh? - 10% All About Eggs in a fraction of second

15. SERP Page Rank???

19. Simple hierarchy Each page has one outgoing link, i.e. C(A) = 1 and C(B) = 1) We don’t know the PR of the pages, lets assume each has PR = 1.00 , d = 0.85 PR(A) = (1 – d) + d(PR(B)/1) PR(B) = (1 – d) + d(PR(A)/1) i.e. PR(A) = 0.15 + 0.85 * 1 = 1 PR(B) = 0.15 + 0.85 * 1= 1 We started out with a lucky guess..! The numbers aren't changing at all..!

20. Complex Hierarchy Average PR : 0.378 PR Loss : 8 – (.92+.41+.41+.41+.22+.22+.22+.22)0.378 = 7.622 For Calculation Click Here

21. Complex Hierarchy with Avg PR = 1.0000 Average PR : 1.0000 PR Loss : 8 – (3.35+1.1+1.1+1.1+.34+.34+.34+.34) = 0.0000

23. DFID 2006

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