Nevertheless, at the time that specific formulas for Internet advertising have been developed - as sponsored links in the search results or contextual advertising with messages adapted to the specific contents of the Web sites-, the increase in the use of these advertising systems has started to show spectacular figures.

Just one example: according to the figures of Google's third quarter 2005 report, their advertising revenues for that period were 1.559 million USD, 99% of total Google revenues for that quarter. And this is only the beginning.

Microsoft and Amazon have already seen the potential of this market and they are already completing its own contextual advertising systems to eat a piece of the enormous pie that will suppose this industry in the next years. In fact, Microsoft launched its Microsoft Ad Center last month and it's for sure that will be a tough competitor to Google and Overture.

There is no doubt that the huge competition that will take place in this industry is good news, as much for the advertisers as for web site publishers. For advertisers, mainly smallest ones, it is the opportunity to develop Internet campaigns at affordable budgets. For publishers, the opportunity, finally, to make their advertising-based Internet business models profitable.