Google ! Literally the king of internet. Offers a wide variety of services that cater to advertisers, publishers as well as end users; like Adsense, Adwords, Webmaster Tools, GMail, Picasa, Earth, Orkut, Blogger, YouTube. With the Google Search Engine being the most widely used.

The second most popular search engine. Some of its major services include Yahoo Mail, Yahoo Photos, Yahoo Answers and the newly launched Yahoo Publisher Network.

Microsoft Network a.k.a MSN. Discuss about Microsoft : the company, its services like MSN Search, Hotmail, the whole bunch of Windows series and the new 'Live' Services.

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