Google (GOOG) has generated most of its income from the Ad Words program. When using it, you choose a group of words that you think will come up in an online search. You agree to pay from 1 cent upwards each time your words are clicked upon. Google uses a bidding war technique with its Ad Words program. The highest bidder per word gets to place its website on the top ten of a search page. That program has been fantastic for Google.
At the same time Yahoo! (YHOO) has taken a different road. It chose to offer display ads on search pages. The ads component added to its revenue stream in 2009, making it number one.
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