Quara.com How Google Serch engines work (click on to read more)
HOW SEARCH ENGINES GATHER AND ORGANIZE DATA
Ever wonder how search engines like Google, Yahoo!, Ask.com, and Microsoft Live Search gather and organize their data so quickly? Behold the wonder of technology!
First, search engines need to gather the data. An automated process (known as spidering) constantly crawls the Internet, gathering Web-page data into servers. Google calls their spider the Googlebot; you could refer to it as a spider, robot, bot, or crawler, but it’s all the same thing. Whatever you call the process, it pulls in masses of raw data and does so continuously.
In the second step, search engines have to index the data to make it usable. For each query performed by a user, the search engines apply an algorithm to decide which listings to display and in what order.
SSGITALK.com (click here to read full article)
How Google Search Works
The Google Search: It happens billions of times a day in the blink of an eye and we can have anything before us our minds can think of!
Crawling & Indexing: The journey of a query starts before we ever type a search, with crawling and indexing the web of trillions of documents.
Google uses software known as Web Crawlers to discover publicly available webpages. The most well-known crawler is called Googlebot. Crawlers look at webpages and follow links on those pages and go from link to link and bring data about those webpages back to Google’s servers.
The web is like an ever-growing public library with billions of books. Google essentially gathers the pages during the crawl process and then creates an index much like the index in the back of a book. The Google index includes information about words and their locations. When we search, at the most basic level, their algorithms look up our search terms in the index to find the appropriate pages.
Algorithms: Algorithms are the computer processes and formulas that take our queries and solve them from thousands of webpages with helpful information. Google uses PageRank Algorithm developed by its founders Sergey Brin and Larry Page. Today Google’s algorithms rely on more than 200 unique signals which include things like the terms on websites, the freshness of content and our region that make it possible to guess what we might really be looking for.