Blog de KingLouis / Pascal

Documents utiles

http://www.webrankinfo.com/google/google.php

http://fr.wikipedia.org/wiki/Google

http://padawan.info/fr/web/comment_fonctionne_google.html

http://www.webrankinfo.com/actualites/200512-google-est-partout.htm

Pourquoi google ?

Historique de google

Histoire de google

Dossiers sur google

Dossier sur google

Il faut parler de :

A l'origine , pourquoi google a-t-il été créé ( historique )

Le fonctionnement de google :
_ page rank
_ mise en cache


Chiffres de google

Comment google rentabilise-t-il : adwords

Concurrents : yahoo et MSN

Autres services de google : gmail , picasa , google earth , blogger ...

A l'avenir ?



Plan

I ) Présentation de google ( moteur de recherche )

1 ) A l'origine , l'idée

2 ) Fonctionnement
_ page rank
_ mise en cache
_ serveurs linux
_ google dance
_ robots qui scannent la page

Schéma explicatif
Etude de la présentation des resultats


2 bis ) Points fort du système ( http://www.linternaute.com/surfer/google/googlekezako.shtml )

3 ) Les résultats , chiffres

4 ) Comment google rentabilise-t-il ?

5 ) La confidentialité du traitement , est-ce que ça va durer ?


II ) Les autres services de google

Gmail
Google Earth
Froogle
Picasa

III ) Concurrents

Yahoo
MSN

__________________________________________

Google is the most used search engine on the Internet . I am gonna tell you about it , why it was created , why it has success then I will also talk about the other services of Google ( not only search engine ) .

I ) Google search engine

1 ) The idea

As you probably know , there are a lot of pages on the Internet ( several billions of pages I think ) , so we need something , a tool , to find the information we are looking fort .

Before Google , finding a relevant a information was pretty hard , the other search engines often didn't understand your request .
Google's founders , Larry Page and Sergey Brin , met at Standford university , USA , in 1996 and invented  a mathematic  algorithm  which allowed to get relevant information after a request.
This algorithm is a very important point about Google , it is named , the Page Rank and we'll taked about it later .

The word " google " means the numeral 1 followed by a hundred zeros ( 1 power a hundred ) . It reflects Google's mission to organize the immense amount of information available on the web .

Google was formally created in 1998 ( nineteen ninety eight ).

2 ) How it works

a ) The page rank

The page rank is a mathematic algorithm which gives a note to every page on the web according to its popularity . Then when you make a request , the best-rated pages appear in first .

How does a page get a good note ?
There is a system of vote . If a page A links the page B , it is considerated like a vote fort the page B . So , if a lot of pages link a page , this page will have a good page rank . This system is quite normal : if everybody says that a website is nice , it must be true no ?

That is the main principe of the page rank , there are also other criteria to have a good mark , like the real content of the page , but it stills secret otherwise people would cheat to be in first position .

b) Computers

Google owns a lot of computers ( thousands of computers ) . Most of them are used to give information to the users , when they make a request . The other are used to explorer the Internet and find information .
In fact , Google saves every page he discovers .
Then other computers analyse the content of these pages and gives them a pagerank . So when you make a request , Google doesn't look for the information on the web , but in the pages that it has already saved and analysed .

Some websites are analysed every day , in order to have fresh information .

Schéma :

1 ) Computers explore the web and save the pages
2 ) They analyse the content and the links to determine the page rank
3 ) When a request is made , the give the answer

3 ) Some numbers

In France , 80 % of people use Google ( 60 % in USA )
Google counts 8 billions of pages
3 thousand people work for Google
When you make a request , the answer often comes before half a second
Google owns a hundred thousand computers , based on linux


4) Some useful tips

You can use Google to :
_ view an old copy of a webpage ( > En cache ) , for example if the website has been deleted
_ as a calcultator
_ convert currencies ( 3 euros en dollars )
_ translate a webpage
_ find a definition ( definition de xxx )

5) How do they earn money ?

Using Google is free but , as we saw , Google owns a lot of computers and employes 3 thousand people .

Google earns fifty percent of its benefits with the sponsored links we see when we make a request . Here is the process for this links :

1 ) A commercial website defines how many clics he wants to buy and gives his keywords
2 ) When a user makes a request , the ads appears on the right or on the top
3 ) If the user clicks on the ads , he is sent on the commercial website and Google earns money

Google's benefit is 3 hundred fifty millions dollar .

6 ) Google's good points :

_ very simple to use
_ relevant results
_ very quick
_ useful functions

7 ) Google's weakness

_ as it takes time to analyse and sort pages , a new website only appears in Google one month after its creation

II ) Other google's services

1 ) Gmail is a webmail built on the idea that you should never have to delete your e-mail . The key features are :
_ 2,6 Go ( giga byte ) of space
_ a powerful search engine
_ no agressive ads , only relevant text ads

2 ) Google News gathers a lot of fresh news from every type of website ( popular or personal ) .

3 ) Google Earth allows you to have a skyview of your house , just by writing your adress

4 ) Froogle is for shopping , it compares the price for commercial products

Conclusion

Google is a very intelligent and powerful tool which is for the moment the most used search engine . But in the future , will its new services have the same success ? Then , Google's competitors , MSN and Yahoo , are improving their search engines , will they get to Google's level ?