search engine history and algorithm

8/7/2019 Search Engine History and Algorithm

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Seminar on

Arijit Roy

B.Tech, 6th Semester

Enrolment No: 0810407

Department of CSE


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` Searc engines

` es of searc engine

` How t e work

` lgorit ms used

` Pros and cons

5/2/2011 2search engine history and algorithm


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A program t at searc es documents for

specified ke words and returns a list of t e documents

w ere t e ke words were found.

A web searc engine is designed to searc for

information on t e World Wide Web and F P servers.

e searc results are generall presented in a list of

results and are often called its. e information maconsist of web pages, images, information and ot er

t pes of files.

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Searc engines look t roug t eir own databases of

information in order to find w at it is t at ou are looking for.

Searc engine is t e popular term for an Information

etrieval (I ) s stem.

Searc ngine is reall a general class ofprograms, t e term is

often used to specificall describe s stems like Google, Alta

Vista and xcite t at enable users to searc for documents on

t e World Wide Web and US newsgroups.



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1970 ARPANET publis ed first.

1984 DNS (Domain Name Server) introduced.

1990 First tool for searc en ine, ARC IE developed by Alan Emta e

1993 Wit t e rise of Gopher, two new searc programs, Veronica andJug ead were developed.

1994 First full-text crawl based searc engine web crawler.

1998 Google and MSN launc ed

2000 Ya oo was providing searc services based on Inktomi's searc

engine.

2009 Microsoft's rebranded searc engine, ing, was launc ed.


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` Crawler- ased Searc Engines

` Human-Powered Directories

`

H brid Searc Engines" Or Mixed Results



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Web crawlers are a central part of search engines, and details on

their algorithms and architecture are kept as business secrets.


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Crawler based search engines:


Analysis SWD classifier ranking

Semantic WebMetadata

Index

IR IndexerSWD Indexer

Search services

WebServer

Web

Service

Human Machines

The

WEB

Document cache

CandidateURLs

Discovery

Swoogle bot

Bounded web crawler


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Human powered directories:


Submit our website if ou are to be included

Select an appropriate categor for our website to bepotentiall listed under.

Submit a s ort description to t e director for our

website.

A searc looks for matc es onl in t e descriptions

submitted.


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Search algorithm is an algorit m for finding an item wit

specified properties among a collection of items.

Searc engine algorit ms are some of t e most tig tl keptsecrets in t e world.

Searc engines c ange t eir algorit ms man times eac

mont to fig t off "spam.

If people knew t e exact algorit m t en t e could

manipulate rankings as t e please until t e searc results

became so irrelevant t at t e searc engine became junk.



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` A document processor

` A quer processor

` A searc and matc ing function

` A ranking capabilit

` Summarizing and Presenting documents.



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Consider ( cat at mat )

Select a word from quer ( cat )

Retrieve t e list for t e word cat

Process t e list and for eac document add weig ts to t eaccumulatorbased on TF,ITF, doc lengt .

Find t e best ranked document and look up t e mapping table.

Retrieve and Summarize t e docs.



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Variety:An Internet searc can generate a variet of sources for information. This

variet allows an one searching for information to choose the t pes of

sources the would like to use, or to use a variet of sources to gain a

greater understanding of a subject.

Precision:Search engines do have the abilit to provide refined or more

precise results. Putting quotations marks around a set of words will

bring up results with the exact same words, excluding others.

Organization:

Search engines aid in organizing the vast amount of information

that can sometimes be scattered in various places on the same web

page into an organized list that can be used more easil .



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You get laz and dependent on net.

You get even what ou should not get.

Eas access to the so called bad or restricted stuffs.



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Search engine pla s important role in accessing the contentover the internet, it fetches the pages requested b the user.

It made the internet and accessing the information just a

click awa .

The need for better search engines onl increases.

The search engine sites are among the most popularwebsites.



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` Voice Command Search.

`

Graphical SearchResult.

Scopes in this field are getting higher andhigher b the passing da s.



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search engine history and algorithm

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