Google Adwords
Google Adwords is the most popular form of PPC advertising. You bid for position with the highest bidder obtaining “pole position” at the very top of the results list, or at the top of the right-hand side of the “paid search results” section.
You also stipulate a maximum spend for a given period and thus retain control of your wallet. In addition, the program allows you to run Multivariate testing and automatically switches to the better performing ad when the analytics achives statistical significance.

