How search engine work...

1. SEARCH ENGINES - Prepared By Chinmay Patel [09BCE038] - Under guidance of Dr. Sanjay Garg

3. Different search engines

4. History

5. Working of search engines

6. Web crawlers

12. How web search engine works High-level architecture of a standard Web crawler

15. When a user enters a query into a search engine the engine examines its index and provides a listing of best-matching web pages according to its criteria, usually with a short summary containing the document's title and sometimes parts of the text.

17. The engine looks for the words or phrases exactly as entered.

18. Some search engines provide an advanced feature called proximity search which allows users to define the distance between keywords.

20. While there may be millions of web pages that include a particular word or phrase, some pages may be more relevant, popular, or authoritative than others.

21. Most search engines employ methods to rank the results to provide the "best" results first.

23. Most Web search engines are commercial ventures supported by advertising revenue and , as a result , some employ the practice of allowing advertisers to pay money to have their listings ranked higher in search results.

24. Some search engines which do not accept money for their search engine results make money by running search related ads alongside the regular search engine results.

29. They continuously keep on crawling the web and find new web page that have been added to the web ,pages that have been removed from the web.

30. When you query a search engine to find information, it is actually searching through the database which it has created and not actually searching the Web. Therefore result is provided within sort span of time by search engine.

31. They will begin with a popular site,indexing the words on its page and following every link found within site.

33. It built its initial system to use multiple spiders,usually 3 at a time.

34. Each spider could keep 300 connections to web pages open at a time.

35. At its peak performance,its system can crawl over 100 pages per second , generating around 600 kilobytes of data each second.

37. It was built to index every significant word on a page,leaving out the articles a,an, and the.

38. Differents approaches usually attempt to make the spider operate faster and efficiently.

39. Some spider will keep track of the words in the title,sub-headings and links,along with 100 most frequently used words on the page and each word in the first 20 lines of text.

42. Google provides some special commands that we can use to get more specific results back from searches.

44. Another of the basic commands is the OR operator. If we write [+hotels OR resorts] and we'll notice that the results produce just that : web pages for either key phrase: hotels or resorts.