How do websites like google,facebook earn..?

[Himanshu A]

[Lokesh Chaitanya]

Through ads

[Anil]

by advertisement
u can see ads by Google on any site
and face is also earn by adds as well as gaming

[Vijay]

they earn through the ads posted on those sites

[crookedsuit981]

Facebook earns money by charging for Facebook credits which so many people buy in order to play games all day.

Google earns through its many SEO tools such as Google Adsense and others.

In addition to these main ways, each also has pay-per-click ads that pay the companies a few cents per each click on an advertisement.

[Eprofit Booster]

Google run by NGO which is devoted to the public service. NGO mostly run by the donation and taking some project. other source of income is ads.

[Kevin]

the major source of earning is ads for such websites.

[Anuj]

Well Google's corporate philosophy embodies such casual principles as "you can make money without doing evil," "you can be serious without a suit," and "work should be challenging and the challenge should be fun."
http://www.google.com/corporate/tenthings.html

Google does display advertisements. Haven't you seen "sponsored links" everytime you search for something on Google. These companies pay Google to put their links in highlight on certain search keywords. Like searching for "Blog" shows Blogger.com and Typepad.com in highlighted links.

Also, it earns through Adsense. Have you seen text ads on blogs and websites these days? Whenever you click through these ads, the advertiser pays some money to Google. Also Google pays some part of money to the guy who owns the website. This is a great source of money as Google is also earning money for ads on other websites and blogs.

They get there money from the Pay per clicks... when ever you click on a paid link (they are always on top or side) from a search engine... like if you search for (shoes), companies like addidas and nike pay to be in the the top spots and the reason search engines make so much money is because they dont just set a price. They let the companies bid on the spots so a number one spot for (shoes) could cost a company from $0.5 to $10 everytime you click on there website's link. So they are making millions a day from this.

Google's initial public offering (IPO) took place five years later on August 19, 2004. The company offered 19,605,052 shares at a price of $85 per share.
http://money.cnn.com/2004/04/29/technology/google/
http://www.washingtonpost.com/wp-dyn/art...Aug19.html

You might not imagine, but this adds up to huge amounts of money, Real Huge!

Look at this Links ::
http://investor.google.com/financial/tables.html
http://www.sec.gov/Archives/edgar/data/1...toc95279_8
http://www.google.com/intl/en/corporate/history.html#13
http://www.google.com/intl/en/corporate/history.html#13

About Facebook
Facebook is world’s most popular social networking website getting really high traffic per day. According to Alexa Facebook is no. 4 website in world in terms of traffic it gets. Facebook puts advertising in its site that does not look like ads, they look like part of their site. Facebook is also planning to sell their user data to corporation so they can advertise on your information based and you will see more targeted ads in Facebook.
Site like Facebook that get this type of high traffic from all over the world can easily earn lot of money, they don’t need to find advertisers, they just need to find out quality advertiser from huge list so they can keep Facebook beautiful.
http://www.allfacebook.com/facebook-makes-money-2010-01
http://ezinearticles.com/?How-to-Earn-Mo...id=1089358
http://economictimes.indiatimes.com/info...063819.cms