AdWords differs from traditional forms of advertising. It doesn't come with price lists or rate cards. Instead, our standard pricing model relies on a cost-per-click (CPC) based auction. You'll start by choosing a daily budget you're comfortable with, and then change it at any time. There's no minimum spend and you're not locked into a contract. With Google Adwords, you only pay for results. With ads on Google you're not charged when your ad is displayed, but only when someone clicks on your ad to go to your website. In other words, you only pay when your advertising works.
Google AdSense is a program run by Google that allows publishers in the Google Network of content sites to serve automatic text, image, video, or interactive media advertisements, that are targeted to site content and audience. These advertisements are administered, sorted, and maintained by Google. They can generate revenue on either a per-click or per-impression basis. Google beta-tested a cost-per-action service, but discontinued it in October 2008 in favor of a DoubleClick offering (also owned by Google).In Q1 2014, Google earned US $3.4 billion ($13.6 billion annualized), or 22% of total revenue, through Google AdSense.AdSense is a participant in the AdChoices program, so AdSense ads typically include the triangle-shaped AdChoices icon.