How Google Search Engine work?

Google Search Engine

1. What is search engine?

2. How Google work?

- Google web crawler

- Google indexer

- Google query processor

What is a Search engine?

Search engine:

A website dedicated to search other

websites and there contents.

A program that searches documents

for specified keywords.

It returns a list of the documents

where the keywords were found.

Google web crawlerA 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.

( hình 1 xuất hiện trước -> biến mất, hình 2 xh! )

Google web crawlerSpiders only can follow links from one page to another and from one site to another.

Video 1

Google indexer

Google indexer

Googlebot gives the indexer the full text of the pages it finds.

These pages are stored in Google’s index database.

Video 2

Google query processorGoogle considers over a hundred factors in computing a PageRank and determining which documents are most relevant to a query.

Google query processor

Video 3

Google query processorThe life span of a Google query normally lasts less than half a second, yet involves a number of diferrerent steps that must be completed before results can be delivered to a person seeking information.