Inside google search - how it works??


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Google's search engine is a powerful tool. Without search engines like Google, it would be practically impossible to find the information you need when you browse the Web. Like all search engines, Google uses a special algorithm to generate search results. While Google shares general facts about its algorithm, the specifics are a company secret. This helps Google remain competitive with other search engines on the Web and reduces the chance of someone finding out how to abuse the system

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Inside google search - how it works??

  2. 2. CONTENTS 1. What is search engine? 2. Examples of search engine 3. Google introduction 4. What happens when we do a web search? 5. Spiders and crawlers 6. Googlebot 7. Google’s Query Processor 8. Google’s Indexer 9. Advantages 10.Disadvantages 11.Conclusion 12.Reference
  3. 3. WHAT IS A SEARCH ENGINE? Search engine: It is a website dedicated to search other websites and there contents. It is a program that searches documents for specified keywords. It returns a list of the documents where the keywords were found.
  4. 4. EXAMPLES OF SEARCH ENGINE. There are many search engines but some of the most popular search engines are: Google Yahoo  Alta Vista. Dogpile Bing. etc
  5. 5. GOOGLE INTRODUCTION.  They thought that a search engine that could analyze the relationships between websites would product better results than other search engine.  They called their new creation "BackRub", because it checked the backlinks to estimate a site's importance. The logo they had then was much different from today's logo, and the name was changed in September 7, 1998, when Larry Page and Sergey Brin bought the domain, and officially changed the name to Google.
  6. 6. . Google was a research project in 1996 by Larry Page and Sergey Brin, who were both PhD students at Stanford University Today, Google is a publicly traded company that handles one of the most used search engines in the world. The company currently employs 8,000 employees, and is based in Mountain View, California.
  7. 7. It also has several other headquarters in places like Seattle, Washington. Google offers many innovative services, such as Blogger, Orkut, and Gmail, and since its introduction in 1996, it offers a wide variety of services, not just search anymore.
  9. 9. When we do a Google search actually we are searching the web, we are searching Google's index of the web. We do this by software programs called spiders. Spiders start fetching a few web pages and then they follow the link and fetch the pages they point to.
  10. 10. SPIDERS OR CRAWLERS. A spider, also known as a robot or a crawler, is actually a program that follows, or "crawls", links throughout the Internet, grabbing content from sites and adding it to search engine indexes. Spiders only can follow links from one page to another and from one site to another. That is the primary reason why links to your site are so important.. Spiders find Web pages by following links from other Web pages, but you can also submit your Web pages directly to a search engine or directory and request a visit by their spider.
  11. 11. GOOGLEBOT Googlebot is Google’s web crawling robot, which finds and retrieves pages on the web and hands them off to the Google indexer. It functions much like our web browser, by sending a request to a web server for a web page, downloading the entire page, then handing it off to Google’s indexer. Googlebot consists of many computers requesting and fetching pages much more quickly than you can with your web browser. Googlebot can simultaneously. request thousands of different pages
  12. 12. GOOGLE’S QUERY PROCESSOR The query processor has several parts, including the user interface (search box), the “engine” that evaluates queries and matches them to relevant documents, and the results formatter. Page rank is Google’s system for ranking web pages. A page with a higher PageRank is deemed more important and is more likely to be listed above a page with a lower Page Rank. Google considers over a hundred factors in computing a PageRank and determining which documents are most relevant to a query, including the popularity of the page, the position and size of the search terms within the page, and the proximity of the search terms to one another on the page.
  13. 13. Google applies machine-learning techniques to improve its performance automatically by learning relationships and associations within the stored data. . For example, the spellingcorrecting system. Google gives more priority to pages that have search terms near each other and in the same order as the query. Google can also match multi-word phrases and sentences.
  15. 15. GOOGLE’S INDEXER. Googlebot gives the indexer the full text of the pages it finds.  These pages are stored in Google’s index database. This index is sorted alphabetically by search term, with each index entry storing a list of documents in which the term appears and the location within the text where it occurs. To improve search performance, Google ignores (doesn’t index) common words called stop words.  Stop words are so common that they do little to narrow a search, and therefore they can safely be discarded.  The indexer also ignores some punctuation and multiple spaces, as well as converting all letters to lowercase, to improve Google’s
  16. 16. Advantages The google search box can be used as a calculator, a mathematical converter and a dictionary. It can also be used to find airport conditions, track airline flights, find stock information, look up information in white and yellow pages and get movie listings from your home location.  You can look up Universal product codes and VIN numbers to get vehicle information. Google has options for image search, article search or even search for any government document. It searches according to the terms you type and also searches for other terms with same meaning. It is fast, reliable, it has its own dictionary, calculator, and spell check.
  17. 17. Disadvantages It doesn’t support full Boolean searching. You can only make use of the default AND, the forced AND and the OR terms in your search. It only indexes the first 101 kilobytes of a web page. Another search engine, Yahoo for example, indexes up to 500 kilobytes in the text of web pages Although it does stem words, it doesn’t allow for truncation. You can’t put in part of a word and get Google to “guess the rest”. Google isn’t good for most “deep web” searches, which is why libraries subscribe to unique databases. However, Google is improving in some specialized areas such as Google scholar which searches scholarly document, Google book search which searches the full text of thousands of books and “find in a library” which searches the OCLC database. OCLC stands for online computer library centre and is a worldwide library cooperative.
  18. 18. Reference      
  19. 19. Conclusion It can be concluded that the algorithm of Google search, Spamming protection over links, how websites are indexed, crawled to Google servers, How one can maintain their website through Google Webmaster Tools.