How google works and functions: A complete Approach
1. Lets Unleash The Secret Behind
Search Engine Giant
Presented by:
Prakhar Gethe
(CEO and Co-Founder Team Zenith)
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Facts About Google
How A Search Engine Works
** Types Of search engine
How Google Works
** Google Architecture
** Google Web Crawler
** Google indexer
** Google Query Processor
Goole Working Info graphic
What Is Seo
** SEO techniques
What Is Google Digging
** Methods Of Google Digging
Technology Requirements Of Creating
Search Engine
TOPICS TO BE COVERED
3. FACTS ABOUT GOOGLE
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• Google was founded by Larry Page and Sergey Brin while they were Ph.D.
students at Stanford University
• Founded on 4th september 1998.
• Google uses approximately 20 petabytes of user-generated data every
day. (Petabytes are estimated at 10 to the 15th power bytes.)
• In June 2006, the Oxford English Dictionary (OED) added “Google” as a
verb
• A Google employee is named a “Googler” while a new team member is
called a “Noogler
• The name ‘Google’ was an accident. A spelling mistake made by the
original founders who thought they were going for ‘Googol’
• The prime reason the Google home page is so bare is due to the fact that
the founders didn’t know HTML and just wanted a quick interface. In fact
it was noted that the submit button was a long time coming and hitting
the RETURN key was the only way to burst Google into life.
• Google has the largest network of translators in the world
• On average, Google has acquired more than one company every week
since 2010.
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• On average, Google has acquired more than
one company every week since 2010.
• Google might be the only company with the
explicit goal to REDUCE the amount of time
people spend on its site.
• The world watches 450,000 years of YouTube
videos each month, over twice as long as
modern humans have existed.
• Google has photographed 5 million miles of
road for its Street View maps
• Google.com, home to arguably the world's
most important internet company, contains 23
markup errors in its code.
5. HOW A SEARCH ENGINE WORKS
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A program that searches for and identifies items in a database that correspond
to keywords or characters specified by the user, used especially for finding
particular sites on the Internet.
Or simply
A search engine is a database system designed to index and categorize internet
addresses, otherwise known as URLs.
FACTS ABOUT SEARCH ENGINES
Search Engine Popularity
The most popular search engines on the web:
Google 55.2%
Yahoo 21.7%
MSN Search 9.6%
AOL Search 3.8%
Terra Lycos 2.6%
AltaVista 2.2%
AskJeeves 1.5%
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Number of Words Used in Search Phrases
2-word phrases 32.58%
3-word phrase 25.61%
1-word phrases 19.02%
4-word phrases 12.83%
5-word phrases 5.64%
6-word phrases 2.32%
7-word phrases 0.98%
When People Search
The breakdown of surfer traffic by day of the week:
Monday 15.31%
Tuesday 15.23%
Thursday 14.73%
Wednesday 14.62%
Friday 14.48%
Saturday 13.08%
Sunday 12.55%
Screen Resolutions
The most popular screen resolutions on the web:
1024 x 768 48.3%
800 x 600 31.7%
1280 x 1024 13.6%
1152 x 864 4.0%
640 x 480 1.0%
1600 x 1200 1.0%
1152 x 870 0.2%
7. TYPES OF SEARCH ENGINES
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Automatic:
These search engines are based on information that is collected,
sorted and analyzed by software programs, commonly referred to as
"robots", "spiders", or "crawlers". These spiders crawl through web
pages collecting information which is then analyzed and categorized
into an "index". When you conduct a search using one of these search
engines, you are really searching the index. The results of the search
will depend on the contents of that index and its relevancy to your
query.
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Directories:
A directory is a searchable subject guide of Web sites that have been
reviewed and compiled by human editors. These editors decide which
sites to list, and, in which categories.
Meta:
Meta search engines use automated technology to gather information
from a spider and then deliver a summary of that information as the
results of a search to the end user.
Pay-per-click (PPC):
A search engine that determines ranking according to the dollar
amount you pay for each click from that search engine to your site.
Examples of PPC search engines are Overture.com and FindWhat.com.
The highest ranking goes to the highest bidder.
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How Do Search Engines Rank Web Pages?
When ranking Web pages, search engines follow specific criteria, which
may vary from one search engine to another. Naturally, they want to
generate the most popular (or relevant) pages at the top of their list.
Search engines will look at keywords and phrases, content, HTML meta
tags and link popularity -- just to name a few -- to determine the value of
the Web page.
How Do Search Engines Work?
Search engines compile their databases with the aid of spiders (a.k.a.
robots). These search engine spiders crawl the Internet from link to link,
identifying Web pages. Once search engine spiders find a Web site, they
index the content on those pages, making the URLs available to Internet
users.
In turn, owners of Websites submit their URLs to search engines
for crawling and, ultimately, inclusion in their databases. This is known
as search engine submission.
When you use search engines to find something on the Internet, you're
Basically asking the search engine to scan its database and match your
keywords and phrases with the content of the URLs they have on file
at that time. Spiders regularly return to the URLs they index to look for
changes.When changes occur, the index is updated to reflect the new
information.
10. HOW GOOGLE WORKS
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Google runs on a distributed network of thousands of low-cost computers
and can therefore carry out fast parallel processing. Parallel processing is a
method of computation in which many calculations can be performed
simultaneously, significantly speeding up data processing. Google has three
distinct parts:
Googlebot, a web crawler that finds and fetches web pages.
The indexer that sorts every word on every page and stores the resulting
index of words in a huge database.
The query processor, which compares your search query to the index and
recommends the documents that it considers most relevant.
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Google Architecture
Various Data Structures Used
In
Repository
Lexicon
Document Index
Hit Lists
Forward Index
Inverted Index
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Googlebot, Google’s Web Crawler
Googlebot is Google’s web crawling robot, which finds and retrieves pages on the web and hands them off
to the Google indexer. It’s easy to imagine Googlebot as a little spider scurrying across the strands of
cyberspace, but in reality Googlebot doesn’t traverse the web at all. It functions much like your 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. In fact, Googlebot can request thousands of different pages simultaneously. To
avoid overwhelming web servers, or crowding out requests from human users, Googlebot deliberately
makes requests of each individual web server more slowly than it’s capable of doing.
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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. This data structure allows rapid access to documents
that contain user query terms.
To improve search performance, Google ignores (doesn’t index)
common words called stop words (such as the, is, on, or, of, how, why, as
well as certain single digits and single letters). 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 performance.
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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.
PageRank 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 PageRank.
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. A patent application discusses
other factors that Google considers when ranking a page.
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Let’s see how Google processes a query.
18. SEO-Search Engine Optimization
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Search Engine Optimization is the process of improving the
visibility of a website on organic ("natural" or un-paid)
search engine result pages (SERPs), by incorporating search
engine friendly elements into a website. A successful search
engine optimization campaign will have, as part of the
improvements, carefully select, relevant, keywords which
the on-page optimization will be designed to make
prominent for search engine algorithms.
Search engine optimization is broken down into two basic
areas: on-page, and off-page optimization.
On-page optimization refers to website elements which
comprise a web page, such as HTML code, textual
content, and images.
Off-page optimization refers, predominantly, to
backlinks (links pointing to the site which is being
optimized, from other relevant websites).
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Optimize your title tags
Create compelling meta descriptions
Utilize keyword-rich headings
Add ALT tags to your images
Create a sitemap
Build internal links between pages
Update your site regularly
Image Optimization
URL Optimization
Directory Submission
Commenting
Social Networking
Guest Posting
SEO cont.…
Various SEO techniques:-
20. GOOGLE DIGGING
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The art of searching any content
using google is called Google digging
or the art of googling or sometimes
even Google hacking
Google Dorks or search techniques which can
be used to refine our search
1) Intitle :
2) Filetype :
3) Site :
4) Related
5) Inurl :
22. Technology Requirements Of Creating
Search Engine
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For back-end:-
Asp.Net
PHP
Python
Perl
Or your customized language
For database
• MySql
• Oracle technology
• Any Nosql Databases
• Or any customized database
There are various technologies which can be used to create search engine and
web crawlers ,Bots and query indexer.
For Front-End
• Javascript
• Xml
• JSON
• Dart etc.