If you are interested to know the introduction to the Google Ad Auction, you have to understand that there is not single and fixed rule for it but it is fully scientific system in which advertisers bid for showing ads in publisher's site. Actually, google tries to minimize the cost, which an advertiser has to pay.
If you want to interested its related question and answer, you can read my guide at here.
If you want to interested its related question and answer, you can read my guide at here.
