How Google AdWords ad auction works?

In the video below Hal Varian, to walk you through the AdWords auction and explain how your maximum coist-per-click (CPC) bid and Quality Score determine how much you actually pay for an ad click on Google's search results pages, AdWords blog.

In the video below Hal Varian, to walk you through the AdWords auction and explain how your maximum coist-per-click (CPC) bid and Quality Score determine how much you actually pay for an ad click on Google's search results pages, AdWords blog.